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Sample records for permanent iodine-125 brachytherapy

  1. [Permanent iodine-125 implants brachytherapy: results after 10 years of experience in Liège University Hospital].

    PubMed

    Hermesse, J; Nickers, P; Reul, O; Coucke, P

    2014-01-01

    Permanent implant iodine-125 brachytherapy is an attractive treatment option for men with localized prostate cancer and is an alternative approach to radical prostatectomy. Overall survival and biochemical relapse free survival are similar with both treatments but the toxicity is different. More potency preservation, less incontinence and one day hospitalisation are attractive for the patient with brachytherapy. On the other side, pre-existing obstructive or irritative urinary symptoms at baseline have to guide the patient to a surgical approach. A patient has to be able to select one of these two therapeutic opportunities through a complete transparent information. In this paper, we related our permanent implant iodine-125 brachytherapy experience. Overall survival, biochemical relapse free survival and registred toxicity are similar to those published in the literature.

  2. Permanent Iodine-125 Interstitial Planar Seed Brachytherapy for Close or Positive Margins for Thoracic Malignancies

    SciTech Connect

    Mutyala, Subhakar; Stewart, Alexandra; Khan, Atif J.; Cormack, Robert A.; O'Farrell, Desmond; Sugarbaker, David; Devlin, Phillip M.

    2010-03-15

    Purpose: To assess toxicity and outcome following permanent iodine-125 seed implant as an adjunct to surgical resection in cases of advanced thoracic malignancy. Methods and Materials: An institutional review board-approved retrospective review was performed. Fifty-nine patients were identified as having undergone thoracic brachytherapy seed implantation between September 1999 and December 2006. Data for patient demographics, tumor details, and morbidity and mortality were recorded. Results: Fifty-nine patients received 64 implants. At a median follow-up of 17 months, 1-year and 2-year Kaplan-Meier rates of estimated overall survival were 94.1% and 82.0%, respectively. The 1-year and 2-year local control rates were 80.1% and 67.4%, respectively. The median time to develop local recurrence was 11 months. Grades 3 and 4 toxicity rates were 12% at 1 year. Conclusions: This review shows relatively low toxicity for interstitial planar seed implantation after thoracic surgical resection. The high local control results suggest that an incomplete oncologic surgery plus a brachytherapy implant for treating advanced thoracic malignancy merit further investigation.

  3. Analysis of immune status after iodine-125 permanent brachytherapy in prostate cancer

    PubMed Central

    Du, E; Wang, Lin; Li, Chang-ying; Zhang, Chang-wen; Qu, Yan-chun; Liu, Ran-lu; Xu, Yong; Yang, Kuo; Zhang, Zhi-hong

    2017-01-01

    Background Permanent prostate brachytherapy (PPB) is an effective treatment choice for low and intermediate risk prostate cancer (PCa). However, the impact of PPB on tumor immune status is still poorly understood. This study aimed to assess the immune status in PCa patients before and at different time points after PPB (1, 3, 6, and 12 months). Methods Blood was collected from 32 patients with low and intermediate risk PCa and 12 healthy volunteers. The frequency of immunocompetent cells was identified by flow cytometry. The concentration of immunoglobulins and complements was detected by ELISA. Results Various immunocompetent cells were dysregulated in PCa patients compared with healthy volunteers. Peripheral serum prostate-specific antigen (PSA) decreased rapidly at the first month after PPB treatment, and the peripheral serum PSA became very low at 6 months after PPB treatment. CD3+ T cells, CD4+ T cells, CD3-CD16+/56+ natural killer (NK) cells were increased significantly at certain time points after PPB. Although the percentage of the CD8+ T cells did not change markedly, the ratio of CD4/CD8 increased significantly at 3 months after PPB (P=0.0196). There was no influence of PPB on B cells number, but the concentration of immunoglobulins IgM, IgG, and IgA, and complements C3 and C4 in patients increased at some time points after PPB. Conclusion The immunocompetent cells are dysregulated in PCa patients. PPB treatment could effectively kill tumor cells and then stimulate cellular immunity and humoral immunity in PCa patients. PMID:28546760

  4. Prostate-Specific Antigen Bounce After Permanent Iodine-125 Prostate Brachytherapy-An Australian Analysis

    SciTech Connect

    Zwahlen, Daniel R.; Smith, Ryan; Andrianopoulos, Nick; Matheson, Bronwyn; Royce, Peter; Millar, Jeremy L.

    2011-01-01

    Purpose: To report on prostate-specific antigen (PSA) 'bounces' after {sup 125}I prostate brachytherapy to review the relationship to biochemical control and correlate both clinical and dosimetric variables. Methods and Materials: We analyzed 194 hormone-naive patients with a follow-up of {>=}3 years. Four bounce definitions were applied: an increase of {>=}0.2 ng/mL (definition I), {>=}0.4 ng/mL (definition II), {>=}15% (definition III), and {>=}35% (definition IV) of a previous value with spontaneous return to the prebounce level or lower. Results: Using definition I, II, III, and IV, a bounce was detected in 50%, 34%, 11%, and 9% of patients, respectively. The median time to onset was 14-16 months, the duration was 12-21.5 months, and the magnitude of the increase was 0.5-2 ng/mL. A magnitude of >2 ng/mL, fulfilling the criteria for biochemical failure (BF) according to the American Society for Therapeutic Radiology and Oncology Phoenix definition, was detected in 11.3%, 16.9%, 47.6%, and 50% using definitions I, II, III, and IV, respectively; 11 patients (5.7%) had true BF. The PSA bounces occurred earlier than BF (p < 0.001). The prediction of BF remains controversial and is probably unrelated to biochemical control. The only statistically significant factor predictive of a PSA bounce was younger age (definitions I and II). Conclusion: PSA bounces are common after brachytherapy. All definitions resulted in a high number of false-positive calls for BF during the first 2 years. The definition of an increase of {>=}0.2 ng/mL should be preferred because of the lowest number of false-positive results for BF. Patients experiencing a PSA bounce during the first 2 years after brachytherapy should undergo surveillance every 3-6 months. Additional investigations are recommended for elevated postimplant PSA levels that have not corrected by 3 years of follow-up.

  5. Radical prostatectomy versus high dose permanent prostate brachytherapy using iodine-125 seeds for patients with high risk prostate cancer: a matched cohort analysis.

    PubMed

    Park, Dong Soo; Gong, In Hyuck; Choi, Don Kyung; Hwang, Jin Ho; Shin, Hyun Soo; Oh, Jong Jin

    2013-12-01

    To compare the biochemical outcomes reported after radical prostatectomy (RP) versus high dose permanent prostate brachytherapy (HDPPB) using iodine-125 seeds in the treatment of matched high risk prostate cancer (HiPCa). In this retrospective review, 55 HiPCa patients treated between March 2006 and August 2011, who underwent HDPPB using iodine-125 seeds combined with external beam radiation therapy (EBRT) or androgen deprivation therapy (ADT), were compared with 55 HiPCa patients who underwent RP. Patients were matched for age, prostate-specific antigen (PSA), clinical stage, and Gleason scores. The biochemical outcomes after HDPPB and RP were compared via Kaplan-Meier analysis. Of the 110 patients analyzed, the mean ages, PSA, and Gleason biopsy scores were similar between the two cohorts. Among patients who underwent HDPPB, 20 patients (36.4%) had received adjuvant EBRT. Of this subsample, most patients (98.2%) had received adjuvant ADT for 3 months. Among patients with RP, 20 patients (36.4%) had received adjuvant EBRT, whereas 28 patients had received adjuvant ADT. The mean implanted seed numbers were 92.8, the mean D90 was 218.7 Gy, and the mean V100 was 96.1% after HDPPB. With regard to oncological outcomes, biochemical disease-free survival rates were similar between the two cohorts (82.6 vs. 81.1%, p = 0.982). Urethrorectal fistula developed in one patient with HDPPB. RP and HDPPB, using iodine-125 seeds with combined treatment modalities, exhibited similar biochemical recurrence-free survival rates among HiPCa patients. Further prospective studies with greater sample sizes and longer follow-up periods are needed to validate these results.

  6. American Brachytherapy Society recommends no change for prostate permanent implant dose prescriptions using iodine-125 or palladium-103.

    PubMed

    Rivard, Mark J; Butler, Wayne M; Devlin, Phillip M; Hayes, John K; Hearn, Robert A; Lief, Eugene P; Meigooni, Ali S; Merrick, Gregory S; Williamson, Jeffrey F

    2007-01-01

    In 2004, the American Association of Physicists in Medicine (AAPM) issued a report outlining recommended 125I and 103Pd datasets for consistency in calculating brachytherapy dose distributions. In 2005, to aid evaluating the clinical impact of implementing these datasets, the AAPM assessed the historical dependence of how prescribed doses differed from administered doses for 125I and 103Pd for permanent implantation of the prostate. Consequently, the American Brachytherapy Society (ABS) considered the nature of these changes towards issuing recommended dose prescriptions for 125I and 103Pd interstitial brachytherapy implants for monotherapy and standard boosts. An investigation was performed of the 2005 AAPM analysis to determine changes in administered dose while affixing prescribed dose using 2004 AAPM 125I and 103Pd brachytherapy dosimetry datasets for prostate implants. For 125I and 103Pd, administered dose would change by +1.4% and +4.2%, respectively. The biological and societal impact of changing prescribed dose was considered. Based on the need for clinical constancy and in recognition of overall uncertainties, the ABS recommends immediate implementation of the 2004 AAPM consensus brachytherapy dosimetry datasets and no changes to 125I and 103Pd dose prescriptions at this time. Radiation oncologists should continue to prescribe monotherapy doses of 145 Gy and 125 Gy for 125I and 103Pd, respectively, and standard boost doses of 100-110 Gy and 90-100 Gy for 125I and 103Pd, respectively.

  7. Phase I Trial of Gross Total Resection, Permanent Iodine-125 Brachytherapy, and Hyperfractionated Radiotherapy for Newly Diagnosed Glioblastoma Multiforme

    SciTech Connect

    Chen, Allen M.; Chang, Susan; Pouliot, Jean; Sneed, Penny K.; Prados, Michael D.; Lamborn, Kathleen R.; Malec, Mary K.; McDermott, Michael W.; Berger, Mitchell S.; Larson, David A.

    2007-11-01

    Purpose: To evaluate the feasibility of gross total resection and permanent I-125 brachytherapy followed by hyperfractionated radiotherapy for patients with newly diagnosed glioblastoma. Methods and Materials: From April 1999 to May 2002, 21 patients with glioblastoma multiforme were enrolled on a Phase I protocol investigating planned gross total resection and immediate placement of permanent I-125 seeds, followed by postoperative hyperfractionated radiotherapy to a dose of 60 Gy at 100 cGy b.i.d., 5 days per week. Median age and Karnofsky performance status were 50 years (range, 32-65 years) and 90 (range, 70-100), respectively. Toxicity was assessed according to Radiation Therapy Oncology Group criteria. Results: Eighteen patients completed treatment according to protocol. The median preoperative tumor volume on magnetic resonance imaging was 18.6 cm{sup 3} (range, 4.4-41.2 cm{sup 3}). The median brachytherapy dose measured 5 mm radially outward from the resection cavity was 400 Gy (range, 200-600 Gy). Ten patients underwent 12 reoperations, with 11 of 12 reoperations demonstrating necrosis without evidence of tumor. Because of high toxicity, the study was terminated early. Median progression-free survival and overall survival were 57 and 114 weeks, respectively, but not significantly improved compared with historical patients treated at University of California, San Francisco, with gross total resection and radiotherapy without brachytherapy. Conclusions: Treatment with gross total resection and permanent I-125 brachytherapy followed by hyperfractionated radiotherapy as performed in this study results in high toxicity and reoperation rates, without demonstrated improvement in survival.

  8. Safety and efficacy of iodine-125 permanent prostate brachytherapy in patients with J-pouch anastomosis after total colectomy for ulcerative colitis.

    PubMed

    Cherian, Sheen; Kittel, Jeffrey A; Reddy, Chandana A; Kolar, Matthew D; Ulchaker, James; Angermeier, Kenneth; Stephans, Kevin L; Tendulkar, Rahul D; Klein, Eric; Ciezki, Jay P

    2015-01-01

    To ascertain the safety and efficacy of permanent prostate brachytherapy (PPB) in early prostate cancer patients who have undergone previous total proctocolectomy and J-pouch anastomosis for inflammatory bowel disease. We identified 10 patients with a previous history of prostate cancer and J-pouch anastomosis from our institutional review board-approved database. Seven patients had PPB and 3 had prostatectomy. Only patients treated with PPB were included. Patient records were reviewed to collect data on treatment-related toxicity and oncological outcomes. All 7 patients who underwent PPB had low- to intermediate-risk prostate cancer. The mean prostatic volume was 24.40 mL and the average number of iodine-125 seeds implanted was 84. Postimplant dosimetric calculations showed a mean prostate volume receiving 100% of the prescribed dose (V100) of 88.76%, V150 of 45.23%, V200 of 16.79%, radiation dose delivered to 90% of the prostate of 147.89 Gy, volume of ileal pouch receiving 100% of the prescribed dose of 0.164 mL, and volume of ileal pouch receiving 50% of the prescribed dose of 1.38 mL. After a mean follow-up of 19 months, none of the patients had evidence of biochemical failure or clinical failure. There were no long-term genitourinary side effects detected. Two patients had Common Terminology Criteria for Adverse Events version 4.0 grade II gastrointestinal side effects, of which symptoms resolved to baseline in 1 patient, whereas the other patient progressed to chronic active enteritis (pouchitis). Low- to intermediate-risk prostate cancer patients with J-pouch anastomosis after total colectomy for inflammatory bowel disease are candidates for definitive treatment with PPB. Caution should be exercised while deploying the most posterior row of seeds to minimize enteral pouch radiation doses. Copyright © 2015 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

  9. Iodine-125 brachytherapy for brain tumours - a review

    PubMed Central

    2012-01-01

    Iodine-125 brachytherapy has been applied to brain tumours since 1979. Even though the physical and biological characteristics make these implants particularly attractive for minimal invasive treatment, the place for stereotactic brachytherapy is still poorly defined. An extensive review of the literature has been performed, especially concerning indications, results and complications. Iodine-125 seeds have been implanted in astrocytomas I-III, glioblastomas, metastases and several other tumour entities. Outcome data given in the literature are summarized. Complications are rare in carefully selected patients. All in all, for highly selected patients with newly diagnosed or recurrent primary or metastatic tumours, this method provides encouraging survival rates with relatively low complication rates and a good quality of life. PMID:22394548

  10. Accurate and efficient detection of pulmonary seed embolization in prostate iodine-125 permanent brachytherapy with a collimated gamma scintillation survey meter.

    PubMed

    Chen, Qin-Sheng; Blair, Henry F

    2003-05-01

    Pulmonary seed embolization is frequently observed in permanent prostate brachytherapy. Postoperative chest radiographic examination does not always detect seed embolization. To overcome this deficiency, a low energy gamma scintillation survey meter was converted to a seed-migration detector by adding a cone-shaped single-hole collimation cap to the window end of the scintillation probe. The response functions of the seed-migration detector to iodine-125 (I-125) for different source-to-detector distances in air and in water were measured. The spatial discrimination power of the survey meter, represented by the full width at half maximum measured in water, is typically improved from more than 7 cm to about 3 cm. Seventy-nine patients with I-125 implantation were scanned with the seed-migration detector at the patients' 30-day postevaluation visit. Fifteen patients showed single-seed embolization to the chest region and four patients displayed two-seed embolization. In other words, 24% of the patients present with embolized seeds. The detection accuracy of each patient was validated by a comprehensive investigation procedure. The comprehensive investigation consists of reviewing the patient's treatment history, orally questioning the patient for possible seed loss via the urethra route outside the hospital, examining all available chest radiographs before and after the seed implantation, and counting the seeds on the postevaluation CT scans. In comparison, examinations relying only on the analysis of postoperative chest radiographs yielded a false-positive detection in four patients and a false-negative detection in two patients. Another advantage of the seed-migration detector is that multiple seed-migration scans can be performed without exposing the patient to any additional radiation, for this device is a passive detector. Our clinical implementation also demonstrated that the seed-migration detector is a convenient and cost-effective method. As a result of this

  11. Urinary and Rectal Toxicity Profiles After Permanent Iodine-125 Implant Brachytherapy in Japanese Men: Nationwide J-POPS Multi-institutional Prospective Cohort Study

    SciTech Connect

    Ohashi, Toshio; Yorozu, Atsunori; Saito, Shiro; Tanaka, Nobumichi; Katayama, Norihisa; Kojima, Shinsuke; Maruo, Shinichiro; Kikuchi, Takashi; Dokiya, Takushi; Fukushima, Masanori; Yamanaka, Hidetoshi

    2015-09-01

    Purpose: To assess, in a nationwide multi-institutional cohort study begun in 2005 and in which 6927 subjects were enrolled by 2010, the urinary and rectal toxicity profiles of subjects who enrolled during the first 2 years, and evaluate the toxicity profiles for permanent seed implantation (PI) and a combination therapy with PI and external beam radiation therapy (EBRT). Methods and Materials: Baseline data for 2339 subjects out of 2354 patients were available for the analyses. Toxicities were evaluated using the National Cancer Institute's Common Terminology Criteria for Adverse Events, and the International Prostate Symptom Scores were recorded prospectively until 36 months after radiation therapy. Results: Grade 2+ acute urinary toxicities developed in 7.36% (172 of 2337) and grade 2+ acute rectal toxicities developed in 1.03% (24 of 2336) of the patients. Grade 2+ late urinary and rectal toxicities developed in 5.75% (133 of 2312) and 1.86% (43 of 2312) of the patients, respectively. A higher incidence of grade 2+ acute urinary toxicity occurred in the PI group than in the EBRT group (8.49% vs 3.66%; P<.01). Acute rectal toxicity outcomes were similar between the treatment groups. The 3-year cumulative incidence rates for grade 2+ late urinary toxicities were 6.04% versus 4.82% for the PI and the EBRT groups, respectively, with no significant differences between the treatment groups. The 3-year cumulative incidence rates for grade 2+ late rectal toxicities were 0.90% versus 5.01% (P<.01) for the PI and the EBRT groups, respectively. The mean of the postimplant International Prostate Symptom Score peaked at 3 months, but it decreased to a range that was within 2 points of the baseline score, which was observed in 1625 subjects (69.47%) at the 1-year follow-up assessment. Conclusions: The acute urinary toxicities observed were acceptable given the frequency and retention, and the late rectal toxicities were more favorable than those of other studies.

  12. Prostate brachytherapy with iodine-125 seeds: radiation protection issues.

    PubMed

    Anglesio, Silvia; Calamia, Elisa; Fiandra, Christian; Giglioli, Francesca Romana; Ragona, Riccardo; Ricardi, Umberto; Ropolo, Roberto

    2005-01-01

    Brachytherapy for prostate cancer by means of permanently implanted 125I sources is a well established procedure. An increasing number of patients all over the world are treated with this modality. When the technique was introduced at our institution, radiation protection issues relative to this technique were investigated in order to comply with international recommendations and national regulations. Particular attention was paid to the need for patient shielding after discharge from hospital. The effective and equivalent doses to personnel related to implantation, the effective dose to patient relatives as computed by a developed algorithm, the air kerma strength values for the radioactive sources certified by the manufacturer compared with those measured by a well chamber, and the effectiveness of lead gloves in shielding the hands were evaluated. The effective dose to the bodies of personnel protected by a lead apron proved to be negligible. The mean equivalent doses to the physician's hands was 420 microSv for one implant; the technician's hands received 65 microSv. The mean air kerma rate measured at the anterior skin surface of the patient who had received an implant was 55 microGy/h (range, 10-115) and was negligible with lead protection. The measured and certified air kerma strength for125I seeds in RAPID Strand corresponded within a margin of +/- 5%. The measured attenuation by lead gloves in operative conditions was about 80%. We also defined the recommendations to be given to the patient at discharge. The exposure risks related to brachytherapy with 125I to operators and public are limited. However, alternation of operators should be considered to minimize exposure. Patient-related measurements should verify the dose rate around the patient to evaluate the need for shielding and to define appropriate radiation protection recommendations.

  13. Incidence and prediction of seed migration to the chest after iodine-125 brachytherapy for hepatocellular carcinoma.

    PubMed

    Lin, Junqing; Yang, Weizhu; Jiang, Na; Zheng, Qubin; Huang, Jingyao; Huang, Ning; Li, Ang; Jiang, Han

    2017-08-08

    The aims were to determine the incidence of seed migration to the chest and to analyze the predictive factors after iodine-125 brachytherapy for hepatocellular carcinoma. Three hundred ninety-nine patients with hepatocellular carcinoma underwent iodine-125 seed brachytherapy. After seed implantation, chest X-ray radiograph or computerized tomography were undertaken to assess the occurrence and location of seed migration at 3 months after brachytherapy. The incidence of seed migration to the lung and heart was calculated. A statistical analysis of the influences of seed loss to the chest was performed between patients with and without seed migration. A total of 13,977 seeds were implanted in 399 patients. One hundred fifty of the 13,977 (1.07%) seeds migrated to the chest in 81 of the 399 (20.30%) patients. Of all the migrated seeds, 112 (74.67%) migrated to the lungs in 59 (67.82%) patients, and 38 (25.33%) seeds migrated to the heart in 28 (47.46%) patients. No case exhibited clinical symptoms related to the migrated seeds. The number of seeds implanted and the number of seed implantations were significantly associated with seed migration. The occurrence of seed migration to the lungs and heart was evaluated. Furthermore, the number of seeds implanted and the number of seed implantation procedures are significant predictors of seed migration. Copyright © 2017 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  14. Complications associated with preoperative radiation therapy and Iodine-125 brachytherapy for localized prostatic carcinoma

    SciTech Connect

    Flanigan, R.C.; Patterson, J.; Mendiondo, O.A.; Gee, W.F.; Lucas, B.A.; McRoberts, J.W.

    1983-08-01

    Twenty-five consecutive patients with localized adenocarcinoma of the prostate treated with 1,050 rad preoperative radiation therapy and Iodine-125 seed brachytherapy are reviewed. Significant long-term postoperative complications included radiation cystitis (12%), radiation proctitis (4%), genital and leg edema (12%), stress incontinence (8%), total incontinence (4%), and impotence (26%). Complications occurred in 75 per cent of patients who received additional postoperative radiation. Improved staging with CT scan, lymphangiography, and Chiba needle biopsy of any possibly abnormal lymph nodes provided excellent preoperative staging with only 1 patient (6%) upstaged at surgery to Stage D1.

  15. Influence of Dose on Risk of Acute Urinary Retention After Iodine-125 Prostate Brachytherapy

    SciTech Connect

    Roeloffzen, Ellen M.A.; Battermann, Jan J.; Deursen, Marijke J.H. van; Monninkhof, Evelyn M.; Visscher, Mareije I.; Moerland, Marinus A.; Vulpen, Marco van

    2011-07-15

    Purpose: To assess the influence of dose on the risk of acute urinary retention (AUR) after iodine-125 prostate brachytherapy. Methods and Materials: Between January 2005 and December 2008, 714 consecutive patients with localized prostate cancer were treated with iodine-125 prostate brachytherapy at our department. All patients completed four imaging studies: magnetic resonance imaging before and 4 weeks after treatment and intraoperative three-dimensional transrectal ultrasonography before and after implantation. The development of AUR was prospectively recorded. The evaluated treatment and dosimetric parameters included prostate volume, number of needles and seeds used, intra- and postoperative prostate edema, percentage of prostate volume receiving 100%, 150%, and 200% of the prescribed dose to the prostate, minimal dose received by 90% of the prostate volume, and percentage of the urethra receiving 100%, 150%, and 200% of the prescribed dose. Logistic regression analysis was used to examine which factors were associated with AUR. Results: Of the 714 patients, 57 (8.0%) developed AUR. On univariate analysis, the following treatment and dosimetric factors were significantly associated with AUR: International Prostate Symptom Score (odds ratio [OR], 2.07, per 10-point increase), preimplant prostate volume (OR, 1.06), postimplant prostate volume (OR, 1.04), number of needles used (OR, 1.09), and number of seeds used (OR, 1.03). On multivariate analysis, the only independent predictive factors for AUR were pretreatment prostate volume (OR, 1.05) and International Prostate Symptom Score (OR, 1.76, per 10-point increase). Patients with a pretreatment prostate volume >35 cm{sup 3} had a 10.4% risk of developing AUR compared with 5.4% for those with a prostate volume of {<=}35 cm{sup 3}. No association was found between any of the dosimetric parameters and the development of AUR. Conclusion: The radiation dose, within the range studied, did not influence the risk of AUR

  16. Survival of patients with advanced pancreatic cancer after iodine125 seeds implantation brachytherapy

    PubMed Central

    Han, Quanli; Deng, Muhong; Lv, Yao; Dai, Guanghai

    2017-01-01

    Abstract Background: Brachytherapy with iodine125-labeled seeds (125I-seeds) implantation is increasingly being used to treat tumors because of its positional precision, minimal invasion, least damage to noncancerous tissue due to slow and continuous release of radioactivity and facilitation with modern medical imaging technologies. This study evaluates the survival and pain relief outcomes of the 125I-seeds implantation brachytherapy in advanced pancreatic cancer patients. Methods: Literature search was carried out in multiple electronic databases (Google Scholar, Embase, Medline/PubMed, and Ovid SP) and studies reporting I125 seeds implantation brachytherapy in pancreatic cancer patients with unresectable tumor were selected by following predetermined eligibility criteria. Random effects meta-analysis was performed to achieve inverse variance weighted effect size of the overall survival rate after the intervention. Sensitivity and subgroups analyses were also carried out. Results: Twenty-three studies (824 patients’ data) were included in the meta-analysis. 125I-seeds implantation brachytherapy alone was associated with 8.98 [95% confidence interval (CI): 6.94, 11.03] months (P < 0.00001) overall survival with 1-year survival of 25.7 ± 9.3% (mean ± standard deviation; SD) and 2-year survival was 17.9 ± 8.6% (mean ± SD). In stage IV pancreatic cancer patients, overall survival was 7.13 [95% CI: 4.75, 9.51] months (P < 0.00001). In patients treated with 125I-seeds implantation along with 1 or more therapies, overall survival was 11.75 [95% CI: 9.84, 13.65] months (P < 0.00001) with 1-year survival of 47.4 ± 22.75% (mean ± SD) and 2-year survival was 16.97 ± 3.1% (mean ± SD). 125I-seeds brachytherapy was associated with relief of pain in 79.7 ± 9.9% (mean ± SD) of the patients. Conclusions: Survival of pancreatic cancer patients after 125I-seeds implantation brachytherapy is found to be 9 months

  17. A Phase III Randomized Trial of the Timing of Meloxicam With Iodine-125 Prostate Brachytherapy

    SciTech Connect

    Crook, Juanita; Patil, Nikhilesh; Wallace, Kris; Borg, Jette; Zhou, David; Ma, Clement; Pond, Greg

    2010-06-01

    Purpose: Nonsteroidal anti-inflammatory medication is used to reduce prostate edema and urinary symptoms following prostate brachytherapy. We hypothesized that a cyclooxygenase-2 (COX-2) inhibitor regimen started 1 week prior to seed implant might diminish the inflammatory response, thus reducing edema, retention rates, and symptom severity. Methods and Materials: From March 2004 to February 2008, 316 men consented to an institutional review board-approved randomized study of a 4-week course of meloxicam, 7.5 mg orally twice per day, starting either on the day of implant or 1 week prior to implant. Brachytherapy was performed using iodine-125 seeds and was preplanned and performed under transrectal ultrasound (TRUS) and fluoroscopic guidance. Prostate volume obtained by MR imaging at 1 month was compared to baseline prostate volume obtained by TRUS planimetry and expressed as an edema factor. The trial endpoints were prostate edema at 1 month, International Prostate Symptom Score (IPSS) questionnaire results at 1 and 3 months, and any need for catheterization. Results: Results for 300 men were analyzed. Median age was 61 (range, 45-79 years), and median TRUS prostate volume was 35.7 cc (range, 18.1-69.5 cc). Median IPSS at baseline was 5 (range, 0-24) and was 15 at 1 month, 16 at 3 months, and 10 at 6 months. Catheterization was required for 7% of patients (6.2% day 0 arm vs. 7.9% day -7 arm; p = 0.65). The median edema factor at 1 month was 1.02 (range, 0.73-1.7). 1.01 day 0 arm vs. 1.05 day -7 arm. Baseline prostate volume remained the primary predictor of postimplant urinary retention. Conclusions: Starting meloxicam 1 week prior to brachytherapy compared to starting immediately after the procedure did not reduce 1-month edema, improve IPSSs at 1 or 3 months, or reduce the need for catheterization.

  18. Iodine-125 Interstitial Brachytherapy for Pediatric Desmoid-Type Fibromatosis of the Head and Neck: A Case Report.

    PubMed

    Wu, Wen-Jie; Guo, Hua-Qiu; Yu, Guang-Yan; Zhang, Jian-Guo

    2017-04-01

    Desmoid-type fibromatosis (DF) is a locally aggressive benign soft tissue tumor. It is rarely observed in the head and neck region and is particularly uncommon in the parotid gland. This report describes the case of a 32-month-old girl with DF of the head and neck. The tumor was resected with gross residual tumors. Recurrence occurred 3 months later and then the patient was treated with iodine-125 interstitial brachytherapy. The tumor was completely absent 6 months after brachytherapy. No recurrence was found 60 months after brachytherapy during follow-up. No severe toxicities or growth abnormalities were observed. Very-low-dose rate brachytherapy as the sole modality could be a reasonable alternative for the treatment of inoperable DF of the head and neck, which avoids the risk of cosmetic deformity caused by surgery, especially in pediatric patients. In addition, long-term follow-up is recommended.

  19. Outcomes of Iodine-125 Plaque Brachytherapy for Uveal Melanoma With Intraoperative Ultrasonography and Supplemental Transpupillary Thermotherapy

    SciTech Connect

    Badiyan, Shahed N.; Rao, Rajesh C.; Apicelli, Anthony J.; Acharya, Sahaja; Verma, Vivek; Garsa, Adam A.; DeWees, Todd; Speirs, Christina K.; Garcia-Ramirez, Jose; Esthappan, Jacqueline; Grigsby, Perry W.; Harbour, J. William

    2014-03-15

    Purpose: To assess the impact on local tumor control of intraoperative ultrasonographic plaque visualization and selective application of transpupillary thermotherapy (TTT) in the treatment of posterior uveal melanoma with iodine-125 (I-125) episcleral plaque brachytherapy (EPB). Methods and Materials: Retrospective analysis of 526 patients treated with I-125 EPB for posterior uveal melanoma. Clinical features, dosimetric parameters, TTT treatments, and local tumor control outcomes were recorded. Statistical analysis was performed using Cox proportional hazards and Kaplan-Meier life table method. Results: The study included 270 men (51%) and 256 women (49%), with a median age of 63 years (mean, 62 years; range, 16-91 years). Median dose to the tumor apex was 94.4 Gy (mean, 97.8; range, 43.9-183.9) and to the tumor base was 257.9 Gy (mean, 275.6; range, 124.2-729.8). Plaque tilt >1 mm away from the sclera at plaque removal was detected in 142 cases (27%). Supplemental TTT was performed in 72 patients (13.7%). One or 2 TTT sessions were required in 71 TTT cases (98.6%). After a median follow-up of 45.9 months (mean, 53.4 months; range, 6-175 months), local tumor recurrence was detected in 19 patients (3.6%). Local tumor recurrence was associated with lower dose to the tumor base (P=.02). Conclusions: Ultrasound-guided plaque localization of I-125 EPB is associated with excellent local tumor control. Detection of plaque tilt by ultrasonography at plaque removal allows supplemental TTT to be used in patients at potentially higher risk for local recurrence while sparing the majority of patients who are at low risk. Most patients require only 1 or 2 TTT sessions.

  20. Brachytherapy of recurrent malignant brain tumors with removable high-activity iodine-125 sources

    SciTech Connect

    Gutin, P.H.; Phillips, T.L.; Wara, W.M.; Leibel, S.A.; Hosobuchi, Y.; Levin, V.A.; Weaver, K.A.; Lamb, S.

    1984-01-01

    Thirty-seven patients harboring recurrent malignant primary or metastatic brain tumors were treated by 40 implantations of high-activity iodine-125 (/sup 125/I) sources. All patients had been treated with irradiation and most had been treated with chemotherapeutic agents, primarily nitrosoureas. Implantations were performed using computerized tomography (CT)-directed stereotaxy; /sup 125/I sources were held in one or more afterloaded catheters that were removed after the desired dose (minimum tumor dose of 3000 to 12,000 rads) had been delivered. Patients were followed with sequential neurological examinations and CT scans. Results of 34 implantation procedures were evaluable: 18 produced documented tumor regression (response) for 4 to 13+ months; five, performed in deteriorating patients, resulted in disease stability for 4 to 12 months. The overall response rate was 68%. In 11 patients, implantation did not halt clinical deterioration. At exploratory craniotomy 5 to 12 months after implantation, focal radiation necrosis was documented in two patients whose tumor had responded initially and then progressed, and in three patients whose disease had progressed initially (four glioblastomas, one anaplastic astrocytoma); histologically identifiable tumor was documented in two of these patients. All improved after resection of the focal necrotic mass and are still alive 10, 15, 19, 24, and 25 months after the initial implantation procedure; only one patient has evidence of tumor regrowth. The median follow-up period after implantation for the malignant glioma (anaplastic astrocytoma and glioblastoma multiforme) group is 9 months, with 48% of patients still surviving. While direct comparison with the results of chemotherapy is difficult, results obtained in this patient group with interstitial brachytherapy are probably superior to results obtained with chemotherapy.

  1. Early treatment of complex located pediatric low-grade gliomas using iodine-125 brachytherapy alone or in combination with microsurgery.

    PubMed

    Kunz, Mathias; Nachbichler, Silke B; Ertl, Lorenz; Fesl, Gunther; Egensperger, Rupert; Niyazi, Maximilian; Schmid, Irene; Tonn, Joerg Christian; Peraud, Aurelia; Kreth, Friedrich Wilhelm

    2016-03-01

    To analyze efficacy, functional outcome, and treatment toxicity of low-dose rate I-125 brachytherapy (SBT) alone or in combination with best safe resection (in case of larger tumor volumes) as first-line treatment for pediatric low-grade gliomas (PLGGs) not suitable for complete resection. Consecutively treated (2000-2014) complex located circumscribed WHO grade I/II PLGGs were included. For small tumors (≤4 cm in diameter) SBT alone was performed; for larger tumors best safe resection and subsequent SBT was chosen. Temporary Iodine-125 seeds were used (median reference dose: 54 Gy). Treatment response was estimated with the modified MacDonald criteria. Analysis of functional outcome included ophthalmological, endocrinological and neurological evaluation. Survival was analyzed with the Kaplan-Meier method. Prognostic factors were obtained from proportional hazards models. Toxicity was categorized according to the Common Terminology Criteria for Adverse Events. Fifty-eight patients were included treated either with SBT alone (n = 39) or with SBT plus microsurgery (n = 19). Five-year progression-free survival was 87%. Two patients had died due to tumor progression. Among survivors, improvement/stabilization/deterioration of functional deficits was seen in 20/14/5 patients, respectively. Complete/partial response had beneficial impact on functional scores (P = 0.02). The 5-year estimated risk to receive adjuvant radiotherapy/chemotherapy was 5.2%. The overall early (delayed) toxicity rate was 8.6% (10.3%), respectively. No permanent morbidity occurred. In complex located PLGGs, early SBT alone or combined with best safe resection preserves/improves functional scores and results in tumor control rates usually achieved with complete resection. Long-term analysis is necessary for confirmation of these results.

  2. SU-E-T-12: A Comparative Dosimetric Study of Pre and Post Prostate Iodine-125 Permanent Seed Implants

    SciTech Connect

    Liu, X; Rahimian, J; Goy, B; Cosmatos, H; Qian, Y

    2015-06-15

    Purpose: Post-implant dosimetry has become the gold standard for prostate implant evaluation. The goal of this research is to compare the dosimetry between pre-plan and post-plan in permanent prostate seed implant brachytherapy. Methods: A retrospective study of 91 patients treated with Iodine-125 prostate seed implant between year 2012∼2014 were performed. All plans were created using a VariSeed 8.0 planning system. Pre-plan ultrasound images were acquired using 0.5 cm slice thickness. Post-plan CT images acquired about 1–4 weeks after implant, fused with the preplan ultrasound images. The prostate and urethra contours were generated using the fusion of ultrasound and CT images. Iodine-125 seed source activities varied between 0.382 to 0.414 mCi per seed. The loading patterns varied slightly between patients depending on the prostate size. Statistical analysis of pre and post plans for prostate and urethra volumes, V100%, V150% and D90, and urethra D10 were performed and reported. Results: The pre and post implant average prostate size was 36.90cc vs. 38.58cc; V100% was 98.33% vs. 96.89%; V150% was 47.09% vs. 56.95%; D90 was 116.35Gy vs. 116.12Gy, urethra volume was 1.72cc vs. 1.85cc, urethra D10% was 122.0% vs. 135.35%, respectively. There was no statistically significant difference between the pre and post-plan values for D90(p-value=0.43). However, there are significant differences between other parameters most likely due to post surgical edema; prostate size (p-value= 0.00015); V100% (p-value=3.7803E-07); V150% (p-value=1.49E-09); urethra volume (p-value= 2.77E-06); Urethra D10 (p-value=7.37E-11). Conclusion: The post-plan dosimetry using CT image set showed similar D90 dose coverage to the pre-plan using the ultrasound image dataset. The study showed that our prostate seed implants have consistently delivered adequate therapeutic dose to the prostate while sparing urethra. Future studies to correlate dose versus biochemical response using patients’ PSA

  3. [Orgasm after curietherapy with permanent iodine-125 radioimplants for localized prostate cancer].

    PubMed

    Delaunay, B; Delannes, M; Salloum, A; Delavierre, D; Wagner, F; Jonca, F; Thoulouzan, M; Plante, P; Bachaud, J-M; Soulie, M; Huyghe, E

    2011-12-01

    Orgasm is a domain of male sexuality that remains underreported in literature. Our aim was to realize the first detailed analysis of orgasm in patients treated by 125 I permanent prostate brachytherapy for localized prostate cancer. In a series of 270 sexually active men treated by prostate brachytherapy (125I permanent implantation), 241 (89%), mean age of 65 (43-80), participated in a mailed survey about sexual function after a mean time of 36 months (9-70). Erectile and ejaculatory functions and orgasm were explored using a mailed questionnaire. Two questions focused on orgasm. The first was about quality of orgasm (fast/intense/late, difficult/weak/absent) and the second about the presence of painful orgasm and its frequency (always/sometimes/often). After prostate brachytherapy, 81.3% of sexually active men conserved ejaculation and 90% orgasm. There was a significant deterioration of the quality of orgasm (P=0.0001). More than 50% of the patients had an altered orgasm (weak, difficult, absent) after brachytherapy, vs 16% before implantation (P=0.001). Men with a diminished ejaculation volume often had a weak/difficult orgasm (P=0.007). Neoadjuvant hormonal therapy did not seem to impact the quality of orgasm or the frequency of painful ejaculation. Patients who had an IIEF-5 score higher than 12 had frequently intense orgasm (26.7% vs 2.7%; P<0.001) after brachytherapy. Sixty patients (30.3%) experienced often/sometimes painful ejaculation 12.9% (n=31) before implantation (P=0.0001). Most of the patients treated by prostate brachytherapy conserved orgasm after treatment. However, most of the patients described a deterioration of the quality of orgasm. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  4. Visual Acuity, Contrast Sensitivity and Color Vision Three Years After Iodine-125 Brachytherapy for Choroidal and Ciliary Body Melanoma

    PubMed Central

    Tsui, Irena; Beardsley, Robert M; McCannel, Tara A; Oliver, Scott C; Chun, Melissa W; Lee, Steve P; Chow, Phillip E; Agazaryan, Nzhde; Yu, Fei; Straatsma, Bradley R

    2015-01-01

    Purpose : To report visual acuity, contrast sensitivity and color vision prior to, 1 year after, 2 years after and 3 years after iodine-125 brachytherapy for choroidal and ciliary body melanoma (CCM). Design : Prospective interventional case series. Participants : Thirty-seven patients (37 eyes) with CCM. Methods : Patients had best-corrected Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity, Pelli-Robson contrast sensitivity and Hardy-Rand-Rittler color vision measurement; comprehensive ophthalmology examination; optical coherence tomography; and ultrasonography at baseline prior to, 1 year after, 2 years after and 3 years after I-125 brachytherapy. Main Outcome Measures : Visual acuity, contrast sensitivity and color vision prior to, 1 year after, 2 years after and 3 years after brachytherapy. Results : Nineteen (19) men and 18 women with mean age of 58 years (SD 13, range 30-78) prior to, 1 year after, 2 years after and 3 years after brachytherapy had mean best-corrected visual acuity of 77 letters (20/32), 65 letters (20/50), 56 letters (20/80) and 47 letters (20/125); contrast sensitivity of 30, 26, 22 and 19 letters; color vision of 26, 20, 17 and 14 test figures, respectively. Decrease in visual acuity, contrast sensitivity and color vision was statistically significant from baseline at 1 year, 2 years, and 3 years after brachytherapy. Decreased acuity at 3 years was associated with mid-choroid and macula melanoma location, ≥ 4.1 mm melanoma height, radiation maculopathy and radiation optic neuropathy. Conclusion : 1, 2 and 3 years after brachytherapy, eyes with CCM had significantly decreased visual acuity, contrast sensitivity and color vision. PMID:26312123

  5. Prostate-specific antigen percentage: An early predictive tool after iodine-125 interstitial brachytherapy for prostate cancer.

    PubMed

    Paoluzzi, Mauro; Losa, Andrea; Cerboneschi, Valentina; Colosimo, Caterina; Fontana, Nicola; Mangili, Paola; Mignogna, Marcello; Nava, Luciano; Ravaglia, Valentina

    2017-06-19

    After interstitial prostate iodine-125 brachytherapy (BT), prostate-specific antigen (PSA) evolution in time could predict overall biochemical relapse, but, considering the single patient, it is influenced by the presentation PSA amount and by the prostatic volume. It is also challenging to differentiate a PSA bounce from a biochemical relapse. To determine the usefulness of PSA percentage (PP) defined as the rate between PSA presented by a patient at time "t" and the PSA that the same patient had presented at the time of diagnosis (t0) assumed as 100% in predicting biochemical relapse and in differentiating them from PSA Bounces. We included 721 patients from Milan S. Raffaele Turro (399) and Lucca Campo di Marte (then S. Luca) Hospital (322). The mean age of patients was 66.5 years (range, 50-79). Mean followup was 150 months (range, 24-180). For each patient, PSA was recorded before and after iodine-125 BT, and PPs were calculated. Cox regression model, relative operating characteristic curves, and Kaplan-Meier regression model were elaborated, and a cutoff of 20% was defined. We observed that PP >20% is an independent variable highly associated with relapse risk (p < 0.0001) with a sensitivity of 79.7%, a specificity of 82%, and an hazard ratio of 12.1, since the 6 months of followup. A PSA increase above the nadir should be because of bounce (sensitivity and specificity of 81.4%, p < 0.0001) if patient had experienced at 6 months a PP <20%. PP might represent an early and useful tool, predictive of clinical outcome in patients after BT for prostate cancer. Copyright © 2017 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  6. Ocular Response of Choroidal Melanoma With Monosomy 3 Versus Disomy 3 After Iodine-125 Brachytherapy

    SciTech Connect

    Marathe, Omkar S.; Wu, Jeffrey; Lee, Steve P.; Yu Fei; Burgess, Barry L.; Leu Min; Straatsma, Bradley R.; McCannel, Tara A.

    2011-11-15

    Purpose: To report the ocular response of choroidal melanoma with monosomy 3 vs. disomy 3 after {sup 125}I brachytherapy. Methods and Materials: We evaluated patients with ciliochoroidal melanoma managed with fine needle aspiration biopsy immediately before plaque application for {sup 125}I brachytherapy between January 1, 2005 and December 31, 2008. Patients with (1) cytopathologic diagnosis of melanoma, (2) melanoma chromosome 3 status identified by fluorescence in situ hybridization, and (3) 6 or more months of follow-up after brachytherapy were sorted by monosomy 3 vs. disomy 3 and compared by Kruskal-Wallis test. Results: Among 40 ciliochoroidal melanomas (40 patients), 15 had monosomy 3 and 25 had disomy 3. Monosomy 3 melanomas had a median greatest basal diameter of 12.00 mm and a median tumor thickness of 6.69 mm before brachytherapy; at a median of 1.75 years after brachytherapy, median thickness was 3.10 mm. Median percentage decrease in tumor thickness was 48.3%. Disomy 3 melanomas had a median greatest basal diameter of 10.00 mm and median tumor thickness of 3.19 mm before brachytherapy; at a median of 2.00 years after brachytherapy, median tumor thickness was 2.37 mm. The median percentage decrease in tumor thickness was 22.7%. Monosomy 3 melanomas were statistically greater in size than disomy 3 melanomas (p < 0.001) and showed a greater decrease in tumor thickness after brachytherapy (p = 0.006). Conclusion: In this study, ciliochoroidal melanomas with monosomy 3 were significantly greater in size than disomy 3 melanoma and showed a significantly greater decrease in thickness at a median of 1.75 years after brachytherapy. The greater decrease in monosomy 3 melanoma thickness after brachytherapy is consistent with other malignancies in which more aggressive pathology has been shown to be associated with a greater initial response to radiotherapy.

  7. Dosimetric and late radiation toxicity comparison between iodine-125 brachytherapy and stereotactic radiation therapy for juxtapapillary choroidal melanoma.

    PubMed

    Krema, Hatem; Heydarian, Mostafa; Beiki-Ardakani, Akbar; Weisbrod, Daniel; Xu, Wei; Laperriere, Normand J; Sahgal, Arjun

    2013-07-01

    To compare the dose distributions and late radiation toxicities for (125)I brachytherapy (IBT) and stereotactic radiation therapy (SRT) in the treatment of juxtapapillary choroidal melanoma. Ninety-four consecutive patients with juxtapapillary melanoma were reviewed: 30 have been treated with IBT and 64 with SRT. Iodine-125 brachytherapy cases were modeled with plaque simulator software for dosimetric analysis. The SRT dosimetric data were obtained from the Radionics XKnife RT3 software. Mean doses at predetermined intraocular points were calculated. Kaplan-Meier estimates determined the actuarial rates of late toxicities, and the log-rank test compared the estimates. The median follow-up was 46 months in both cohorts. The 2 cohorts were balanced with respect to pretreatment clinical and tumor characteristics. Comparisons of radiation toxicity rates between the IBT and SRT cohorts yielded actuarial rates at 50 months for cataracts of 62% and 75% (P=.1), for neovascular glaucoma 8% and 47% (P=.002), for radiation retinopathy 59% and 89% (P=.0001), and for radiation papillopathy 39% and 74% (P=.003), respectively. Dosimetric comparisons between the IBT and SRT cohorts yielded mean doses of 12.8 and 14.1 Gy (P=.56) for the lens center, 17.6 and 19.7 Gy (P=.44) for the lens posterior pole, 13.9 and 10.8 Gy (P=.30) for the ciliary body, 61.9 and 69.7 Gy (P=.03) for optic disc center, and 48.9 and 60.1 Gy (P<.0001) for retina at 5-mm distance from tumor margin, respectively. Late radiation-induced toxicities were greater with SRT, which is secondary to the high-dose exposure inherent to the technique as compared with IBT. When technically feasible, IBT is preferred to treat juxtapapillary choroidal melanoma. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. Dosimetric and Late Radiation Toxicity Comparison Between Iodine-125 Brachytherapy and Stereotactic Radiation Therapy for Juxtapapillary Choroidal Melanoma

    SciTech Connect

    Krema, Hatem

    2013-07-01

    Purpose: To compare the dose distributions and late radiation toxicities for {sup 125}I brachytherapy (IBT) and stereotactic radiation therapy (SRT) in the treatment of juxtapapillary choroidal melanoma. Methods: Ninety-four consecutive patients with juxtapapillary melanoma were reviewed: 30 have been treated with IBT and 64 with SRT. Iodine-125 brachytherapy cases were modeled with plaque simulator software for dosimetric analysis. The SRT dosimetric data were obtained from the Radionics XKnife RT3 software. Mean doses at predetermined intraocular points were calculated. Kaplan-Meier estimates determined the actuarial rates of late toxicities, and the log–rank test compared the estimates. Results: The median follow-up was 46 months in both cohorts. The 2 cohorts were balanced with respect to pretreatment clinical and tumor characteristics. Comparisons of radiation toxicity rates between the IBT and SRT cohorts yielded actuarial rates at 50 months for cataracts of 62% and 75% (P=.1), for neovascular glaucoma 8% and 47% (P=.002), for radiation retinopathy 59% and 89% (P=.0001), and for radiation papillopathy 39% and 74% (P=.003), respectively. Dosimetric comparisons between the IBT and SRT cohorts yielded mean doses of 12.8 and 14.1 Gy (P=.56) for the lens center, 17.6 and 19.7 Gy (P=.44) for the lens posterior pole, 13.9 and 10.8 Gy (P=.30) for the ciliary body, 61.9 and 69.7 Gy (P=.03) for optic disc center, and 48.9 and 60.1 Gy (P<.0001) for retina at 5-mm distance from tumor margin, respectively. Conclusions: Late radiation-induced toxicities were greater with SRT, which is secondary to the high-dose exposure inherent to the technique as compared with IBT. When technically feasible, IBT is preferred to treat juxtapapillary choroidal melanoma.

  9. Iodine 125 Brachytherapy With Vitrectomy and Silicone Oil in the Treatment of Uveal Melanoma: 1-to-1 Matched Case-Control Series

    SciTech Connect

    McCannel, Tara A. McCannel, Colin A.

    2014-06-01

    Purpose: We initially reported the radiation-attenuating effect of silicone oil 1000 centistokes for iodine 125. The purpose of this report was to compare the clinical outcomes in case patients who had iodine 125 brachytherapy with vitrectomy and silicone oil 1000 centistokes with the outcomes in matched control patients who underwent brachytherapy alone. Methods and Materials: Consecutive patients with uveal melanoma who were treated with iodine 125 plaque brachytherapy and vitrectomy with silicone oil with minimum 1-year follow-up were included. Control patients who underwent brachytherapy alone were matched for tumor size, location, and sex. Baseline patient and tumor characteristics and tumor response to radiation, final visual acuity, macular status, central macular thickness by ocular coherence tomography (OCT), cataract progression, and metastasis at last follow-up visit were compared. Surgical complications were also determined. Results: Twenty case patients met the inclusion criteria. The average follow-up time was 22.1 months in case patients and 19.4 months in control patients. The final logMAR vision was 0.81 in case patients and 1.1 in control patients (P=.071); 8 case patients and 16 control patients had abnormal macular findings (P=.011); and the average central macular thickness by OCT was 293.2 μm in case patients and 408.5 μm in control patients (P=.016). Eleven case patients (55%) and 1 control patient (5%) had required cataract surgery at last follow-up (P=.002). Four patients in the case group and 1 patient in the control group experienced metastasis (P=.18). Among the cases, intraoperative retinal tear occurred in 3 patients; total serous retinal detachment and macular hole developed in 1 case patient each. There was no case of rhegmatogenous retinal detachment, treatment failure, or local tumor dissemination in case patients or control patients. Conclusions: With up to 3 years of clinical follow-up, silicone oil during brachytherapy

  10. Permanent Planar Iodine-125 Implants: The Dosimetric Effect of Geometric Parameters for Idealized Source Configurations

    SciTech Connect

    Cormack, Robert A.

    2007-11-15

    Purpose: To provide dosimetric information about permanent planar {sup 125}I implants in a manner that is useful to the brachytherapist in the operative setting. Methods and Materials: Reference planar permanent implants were simulated for a variety of areas with sources placed uniformly on a 1-cm grid. Implants having variable source spacing and curvature were simulated and compared with the reference implants. Dosimetric measures were calculated at 0.5 and 1.0 cm from the implant plane. Results: A method for calculating dosimetric statistics for permanent implants ranging from 5 x 5 cm to 13 x 13 cm is presented. A formula to predict the reference source strength needed to achieve a desired dosimetric quantity is also presented. The effect of adjusting strand spacing to compensate for source activity is presented and is shown to be an effective means to adjust implants to use source strengths other than the reference strength. The effect of implant curvature compared with flat implants on dosimetric statistics is presented as a function of radius of curvature. Conclusions: The results presented in this work may be used to provide information about dose delivered from planar permanent implants.

  11. Versatile permanent planar implant technique utilizing Iodine-125 seeds imbedded in gelfoam

    SciTech Connect

    Marchese, M.J.; Nori, D.; Anderson, L.L.; Hilaris, B.S.

    1984-05-01

    Tumors attached or adjacent to critical structures can often not be completely resected or resected with adequate surgical margins. Sites involving major blood vessels, the vertebral column or the brain with small residual tumors or suspicious margins often present technical difficulties for standard I-125 or Ir-192 implants. A relatively simple, accurate and inexpensive implant method is decribed using I-125 seeds imbedded in gelfoam to implant permanently into small residual tumors or suspicious margins where standard implant techniques may be unsatisfactory. A method for planning the treatment dose for such an implant is described. Cases involving paraspinal and brain tumors are reported to illustrate the technique.

  12. Outcomes Following Iodine-125 Monotherapy for Localized Prostate Cancer: The Results of Leeds 10-Year Single-Center Brachytherapy Experience

    SciTech Connect

    Henry, Ann M.; Al-Qaisieh, Bashar; Gould, Kathy; Bownes, Peter; Smith, Jonathan; Carey, Brendan; Bottomley, David; Ash, Dan

    2010-01-15

    Purpose: This study reports the 10-year experience of permanent brachytherapy monotherapy at a single UK center. Methods and Materials: Between March 1995 and September 2004, 1,298 patients underwent trans-rectal ultrasound (TRUS) planned transperineal brachytherapy delivering 145 Gy using I-125. No patient received supplemental external beam; 44.2% received neoadjuvant hormones. In 688, CT postimplant dosimetry was available. Outcome data were analyzed in terms of overall survival (OS), disease specific survival (DSS), and PSA relapse-free survival (PSA-RFS). Results: The mean age was 62.9 (range, 34-83) years. Median follow-up was 4.9 years (range, 2.03-11.7 years). OS and DSS were 85% and 95%, respectively, at 10 years. Twenty-one patients died from prostate cancer (1.6%) and 34 (2.5%) from unrelated causes. Seventy-four (5.7%) developed evidence of clinical failure. Overall PSA-RFS was 79.9% and 72.1% at 10 years (American Society for Therapeutic Radiology and Oncology [ASTRO] and Nadir+2 definitions, respectively). Higher presenting PSA or Gleason score and use of neoadjuvant hormones were associated with an increased risk of biochemical failure (p <0.01). Biochemical control was achieved in 86.4%, 76.7%, and 60.6% (ASTRO) and 72.3%, 73.5%, and 57.6% (Nadir+2) of patients in low-, intermediate-, and high-risk groups, respectively. Biochemical control was achieved in 88% of patients with D{sub 90} >=140 Gy and in 78% of patients with D{sub 90} <140 Gy (p <0.01). Conclusions: I-125 brachytherapy alone achieved excellent rates of medium-term biochemical control in both low- and selected intermediate-risk localized prostate cancer patients. Postimplant dosimetry improved with experience and longer follow-up, confirming the relationship of D{sub 90} with biochemical control.

  13. Radiofrequency ablation and percutaneous permanent iodine-125 implantation as salvage therapy for giant recurrent sclerosing epithelioid fibrosarcoma of the chest wall: A case report

    PubMed Central

    KE, SHAN; DING, XUE-MEI; GAO, JUN; WANG, SHAO-HONG; ZHANG, JUN; KONG, JIAN; SUN, WEN-BING

    2015-01-01

    Sclerosing epithelioid fibrosarcoma (SEF) is a rare soft-tissue sarcoma for which there is no standardized treatment regimen available. The current treatment options for SEF are resection, radiation and chemotherapy. Surgical resection remains the mainstay of therapy for SEF. However, SEF is an aggressive tumor that is prone to repeated local recurrence if not widely excised. Radiation and chemotherapy are less commonly used due to the insensitivity of SEF to these therapies. The treatment of recurrent SEF is even more challenging. The present study describes a patient who presented with a giant recurrent SEF arising from the chest wall that was accompanied by emergent bleeding. The patient was a 70-year-old male who had multiple comorbid diseases, including hypertension and chronic cardiac dysfunction. A computed tomography (CT) scan indicated the involvement of the sternum and anterior mediastinum. However, the patient refused any further surgery. Subsequent to careful discussion and consideration, radiofrequency (RF) ablation and percutaneous iodine-125 implantation was administered. The emergent bleeding was successfully stopped and the tumor was eliminated using RF ablation. Percutaneous iodine-125 implantation under CT guidance established effective control on the growth of the tumor involving the mediastinum. Despite this, the tumor recurred 6 months after treatment. The patient refused any further treatment and was discharged. In conclusion, RF ablation and percutaneous permanent iodine-125 implantation is a feasible and safe salvage therapy for patients with recurrent SEF of the chest wall. PMID:26137032

  14. Survival of patients with advanced pancreatic cancer after iodine125 seeds implantation brachytherapy: A meta-analysis.

    PubMed

    Han, Quanli; Deng, Muhong; Lv, Yao; Dai, Guanghai

    2017-02-01

    Brachytherapy with iodine-labeled seeds (I-seeds) implantation is increasingly being used to treat tumors because of its positional precision, minimal invasion, least damage to noncancerous tissue due to slow and continuous release of radioactivity and facilitation with modern medical imaging technologies. This study evaluates the survival and pain relief outcomes of the I-seeds implantation brachytherapy in advanced pancreatic cancer patients. Literature search was carried out in multiple electronic databases (Google Scholar, Embase, Medline/PubMed, and Ovid SP) and studies reporting I seeds implantation brachytherapy in pancreatic cancer patients with unresectable tumor were selected by following predetermined eligibility criteria. Random effects meta-analysis was performed to achieve inverse variance weighted effect size of the overall survival rate after the intervention. Sensitivity and subgroups analyses were also carried out. Twenty-three studies (824 patients' data) were included in the meta-analysis. I-seeds implantation brachytherapy alone was associated with 8.98 [95% confidence interval (CI): 6.94, 11.03] months (P < 0.00001) overall survival with 1-year survival of 25.7 ± 9.3% (mean ± standard deviation; SD) and 2-year survival was 17.9 ± 8.6% (mean ± SD). In stage IV pancreatic cancer patients, overall survival was 7.13 [95% CI: 4.75, 9.51] months (P < 0.00001). In patients treated with I-seeds implantation along with 1 or more therapies, overall survival was 11.75 [95% CI: 9.84, 13.65] months (P < 0.00001) with 1-year survival of 47.4 ± 22.75% (mean ± SD) and 2-year survival was 16.97 ± 3.1% (mean ± SD). I-seeds brachytherapy was associated with relief of pain in 79.7 ± 9.9% (mean ± SD) of the patients. Survival of pancreatic cancer patients after I-seeds implantation brachytherapy is found to be 9 months, whereas a combined treatment with I-seeds brachytherapy and other therapies was

  15. Long-Term Results of Brachytherapy With Temporary Iodine-125 Seeds in Children With Low-Grade Gliomas

    SciTech Connect

    Korinthenberg, Rudolf; Neuburger, Daniela; Trippel, Michael; Ostertag, Christoph; Nikkhah, Guido

    2011-03-15

    Purpose: To retrospectively review the results of temporary I-125 brachytherapy in 94 children and adolescents with low-grade glioma. Methods and Materials: Treatment was performed in progressive tumors roughly spherical in shape with a diameter of up to 5 cm, including 79 astrocytomas, 5 oligodendrogliomas, 4 oligoastrocytomas, 1 ependymoma, and 5 other tumors. Location was suprasellar/chiasmal in 44, thalamic/basal ganglia in 18, hemispheric in 15, midbrain/pineal region in 13, and lower brainstem in 3. Initially, 8% of patients were free of symptoms, 47% were symptomatic but not disabled, and 30% were slightly, 6% moderately, and 3% severely disabled. Results: 5- and 10-year survival was 97% and 92%. The response to I-125 brachytherapy over the long term was estimated after a median observation period of 38.4 (range, 6.4-171.0) months. At that time, 4 patients were in complete, 27 in partial, and 18 in objective remission; 15 showed stable and 30 progressive tumors. Treatment results did not correlate with age, sex, histology, tumor size, location, or demarcation of the tumor. Secondary treatment became necessary in 36 patients, including 19 who underwent repeated I-125 brachytherapy. At final follow-up, the number of symptom-free patients had risen to 21%. Thirty-eight percent showed symptoms without functional impairment, 19% were slightly and 11% moderately disabled, and only 4% were severely disabled. Conclusions: Response rates similar to those of conventional radiotherapy or chemotherapy can be anticipated with I-125 brachytherapy in tumors of the appropriate size and shape. We believe it to be a useful contribution to the treatment of low-grade gliomas in children.

  16. The Impact of Acute Urinary Retention After Iodine-125 Prostate Brachytherapy on Health-Related Quality of Life

    SciTech Connect

    Roeloffzen, Ellen M.A.; Hinnen, Karel A.; Battermann, Jan J.; Monninkhof, Evelyn M.; Roermund, Joep G.H. van; Gellekom, Marion van; Frank, Steven J.; Vulpen, Marco van

    2010-08-01

    Purpose: To evaluate the impact of acute urinary retention (AUR) in patients treated with {sup 125}I prostate brachytherapy on short- and long-term health-related quality of life (HRQOL); and to assess whether pretreatment HRQOL has additional value in the prediction of AUR. Methods and Materials: For 127 patients treated with {sup 125}I brachytherapy for localized prostate cancer between December 2000 and June 2003, toxicity and HRQOL data were prospectively collected. Patients received a HRQOL questionnaire at five time points: before and 1 month, 6 months, 1 year, and 6 years after treatment. The questionnaire included the RAND-36 generic health survey, the cancer-specific European Organization for Research and Treatment of Cancer core questionnaire (EORTC QLQ-C30), the tumor-specific EORTC prostate cancer module (EORTC QLQ-PR25), and the American Urological Association (AUA) symptom index. Results: Of 127 patients, 13 (10.2%) developed AUR. Patients with AUR had a significantly worse urinary QOL at all time points compared with patients without AUR. The mean difference over time (6 years) between both groups for the EORTC QLQ-PR25 urinary symptom score was 13.0 points (p < 0.001) and for the AUA urinary symptom score was 15.7 points (p = 0.001). Global QOL scores (EORTC QLQ-C30) over time for patients who developed AUR were significantly worse compared with patients without AUR (mean difference 6.7 points; p = 0.043). In multivariate logistic regression analysis, pretreatment International Prostate Symptom Score (p = 0.004) and neoadjuvant hormonal treatment (p = 0.034) were predictors of AUR. Quality of life did not have added predictive value. Conclusion: Acute urinary retention after prostate brachytherapy has a significant negative impact on patient's HRQOL up to 6 years after treatment, in terms of both global QOL measures and urinary symptom scores. Furthermore, our results suggest limited value of pretreatment HRQOL measures for the prediction of AUR.

  17. Novel Parameter Predicting Grade 2 Rectal Bleeding After Iodine-125 Prostate Brachytherapy Combined With External Beam Radiation Therapy

    SciTech Connect

    Shiraishi, Yutaka; Hanada, Takashi; Ohashi, Toshio; Yorozu, Atsunori; Toya, Kazuhito; Saito, Shiro; Shigematsu, Naoyuki

    2013-09-01

    Purpose: To propose a novel parameter predicting rectal bleeding on the basis of generalized equivalent uniform doses (gEUD) after {sup 125}I prostate brachytherapy combined with external beam radiation therapy and to assess the predictive value of this parameter. Methods and Materials: To account for differences among radiation treatment modalities and fractionation schedules, rectal dose–volume histograms (DVHs) of 369 patients with localized prostate cancer undergoing combined therapy retrieved from corresponding treatment planning systems were converted to equivalent dose-based DVHs. The gEUDs for the rectum were calculated from these converted DVHs. The total gEUD (gEUD{sub sum}) was determined by a summation of the brachytherapy and external-beam radiation therapy components. Results: Thirty-eight patients (10.3%) developed grade 2+ rectal bleeding. The grade 2+ rectal bleeding rate increased as the gEUD{sub sum} increased: 2.0% (2 of 102 patients) for <70 Gy, 10.3% (15 of 145 patients) for 70-80 Gy, 15.8% (12 of 76 patients) for 80-90 Gy, and 19.6% (9 of 46 patients) for >90 Gy (P=.002). Multivariate analysis identified age (P=.024) and gEUD{sub sum} (P=.000) as risk factors for grade 2+ rectal bleeding. Conclusions: Our results demonstrate gEUD to be a potential predictive factor for grade 2+ late rectal bleeding after combined therapy for prostate cancer.

  18. [Permanent implant prostate cancer brachytherapy: 2013 state-of-the art].

    PubMed

    Cosset, J-M; Hannoun-Lévi, J-M; Peiffert, D; Delannes, M; Pommier, P; Pierrat, N; Nickers, P; Thomas, L; Chauveinc, L

    2013-04-01

    With an experience of more than 25 years for the pioneers (and more than 14 years in France), permanent implant brachytherapy using iodine 125 seeds (essentially) is now recognized as a valuable alternative therapy for localized low-risk prostate cancer patients. The possible extension of the indications of exclusive brachytherapy towards selected patients in the intermediate-risk group has now been confirmed by several studies. Moreover, for the other patients in the intermediate-risk group and for the patients in the high-risk group, brachytherapy, as an addition to external radiotherapy, could represent one of the best ways to escalate the dose. Different permanent implant brachytherapy techniques have been proposed; preplanning or real-time procedure, loose or stranded seeds (or both), manual or automatic injection of the seeds. The main point here is the ability to perfectly master the procedure and to comply with the dosimetric constraints, which have been recently redefined by the international societies, such as the GEC-ESTRO group. Mid- and long-term results, which are now available in the literature, indicate relapse-free survival rates of about 90% at 5-10 years, the best results being obtained with satisfactory dosimetric data. Comparative data have shown that the incontinence and impotence rates after brachytherapy seemed to be significantly inferior to what is currently observed after surgery. However, a risk of about 3 to 5% of urinary retention is usually reported after brachytherapy, as well as an irritative urinary syndrome, which may significantly alter the quality of life of the patients, and last several months. In spite of those drawbacks, with excellent long-term results, low rates of incontinence and impotence, and emerging new indications (focal brachytherapy, salvage brachytherapy after localized failure of an external irradiation), permanent implant prostate brachytherapy can be expected to be proposed to an increasing number of patients

  19. SU-E-T-55: Biological Equivalent Dose (BED) Comparison Between Permanent Interstitial Brachytherapy and Conventional External Beam Radiotherapy for Prostate Cancer

    SciTech Connect

    Liu, X; Rahimian, J; Cosmatos, H; Goy, B; Heywood, C; Qian, Y

    2014-06-01

    Purpose: The goal of this research is to calculate and compare the Biological Equivalent Dose (BED) between permanent prostate Iodine-125 implant brachytherapy as monotherapy with the BED of conventional external beam radiation therapy (EBRT). Methods: A retrospective study of 605 patients treated with Iodine-125 seed implant was performed in which physician A treated 274 patients and physician B treated 331 patients. All the Brachytherapy treatment plans were created using VariSeed 8 planning system. The Iodine-125 seed source activities and loading patterns varied slightly between the two physicians. The prescription dose is 145 Gy to PTV for each patient. The BED and Tumor Control Probability (TCP) were calculated based on the TG 137 formulas. The BED for conventional EBRT of the prostate given in our institution in 2Gy per fraction for 38 fractions was calculated and compared. Results: Physician A treated 274 patients with an average BED of 123.92±0.87 Gy and an average TCP of 99.20%; Physician B treated 331 patients with an average BED of 124.87±1.12 Gy and an average TCP of 99.30%. There are no statistically significant differences (T-Test) between the BED and TCP values calculated for these two group patients.The BED of the patients undergoing conventional EBRT is calculated to be 126.92Gy. The BED of the patients treated with permanent implant brachytherapy and EBRT are comparable. Our BED and TCP values are higher than the reported values by TG 137 due to higher Iodine-125 seed activity used in our institution. Conclusion: We calculated the BED,a surrogate of the biological response to a permanent prostate brachytherapy using TG 137 formulas and recommendation. The TCP of better than 99% is calculated for these patients. A clinical outcome study of these patients correlating the BED and TCP values with PSA and Gleason Levels as well as patient survival is warranted.

  20. Combination of Iodine-125 brachytherapy and chemotherapy for locally recurrent stage III non-small cell lung cancer after concurrent chemoradiotherapy.

    PubMed

    Yu, Xiaojuan; Li, Jin; Zhong, Xiaoming; He, Jingdong

    2015-10-06

    Locally recurrent non-small cell lung cancer (NSCLC) poses a great challenge to physicians. This study aimed to explore the efficacy and safety of the combination of brachytherapy and docetaxel and cisplatin for the treatment of locally recurrent stage III NSCLC. Fifty two patients with locally recurrent stage III NSCLC after concurrent chemoradiotherapy were randomly divided into two groups (n = 26). The patients in experimental group were treated with implantation of radioactive (125)I seeds and DP regimen (docetaxel 60 mg/m(2)/cisplatin 75 mg/m(2)). Patients in control group received DP chemotherapy. The local control rate (LCR), progression-free survival (PFS), and overall response rate (ORR) were defined according to the Response Evaluation Criteria in Solid Tumors (RECIST). With a median follow-up time of 11 months, PFS and LCR was 8 months (95 % CI: 6.99-9.01 months) vs. 5.5 months (95 % CI: 4.43-6.57 months) (P < 0.05) and 10 months (95 % CI: 8.72-11.28 months) vs. 6.2 months (95 % CI: 5.27-7.13 months) (P < 0.05) in the experimental and control groups, respectively. The ORR did not differ between treatment groups and was noted to be 69.2 % and 57.7 %, respectively (P >0.05). There was no occurrence of severe complications in experimental and control groups. The combination of (125)I brachytherapy and second-line chemotherapy is superior to chemotherapy alone and is an effective and safe therapy for this disease. ChiCTR-IOR-15006560.

  1. Monte Carlo calculated doses to treatment volumes and organs at risk for permanent implant lung brachytherapy.

    PubMed

    Sutherland, J G H; Furutani, K M; Thomson, R M

    2013-10-21

    Iodine-125 ((125)I) and Caesium-131 ((131)Cs) brachytherapy have been used with sublobar resection to treat stage I non-small cell lung cancer and other radionuclides, (169)Yb and (103)Pd, are considered for these treatments. This work investigates the dosimetry of permanent implant lung brachytherapy for a range of source energies and various implant sites in the lung. Monte Carlo calculated doses are calculated in a patient CT-derived computational phantom using the EGsnrc user-code BrachyDose. Calculations are performed for (103)Pd, (125)I, (131)Cs seeds and 50 and 100 keV point sources for 17 implant positions. Doses to treatment volumes, ipsilateral lung, aorta, and heart are determined and compared to those determined using the TG-43 approach. Considerable variation with source energy and differences between model-based and TG-43 doses are found for both treatment volumes and organs. Doses to the heart and aorta generally increase with increasing source energy. TG-43 underestimates the dose to the heart and aorta for all implants except those nearest to these organs where the dose is overestimated. Results suggest that model-based dose calculations are crucial for selecting prescription doses, comparing clinical endpoints, and studying radiobiological effects for permanent implant lung brachytherapy.

  2. Monte Carlo calculated doses to treatment volumes and organs at risk for permanent implant lung brachytherapy

    NASA Astrophysics Data System (ADS)

    Sutherland, J. G. H.; Furutani, K. M.; Thomson, R. M.

    2013-10-01

    Iodine-125 (125I) and Caesium-131 (131Cs) brachytherapy have been used with sublobar resection to treat stage I non-small cell lung cancer and other radionuclides, 169Yb and 103Pd, are considered for these treatments. This work investigates the dosimetry of permanent implant lung brachytherapy for a range of source energies and various implant sites in the lung. Monte Carlo calculated doses are calculated in a patient CT-derived computational phantom using the EGsnrc user-code BrachyDose. Calculations are performed for 103Pd, 125I, 131Cs seeds and 50 and 100 keV point sources for 17 implant positions. Doses to treatment volumes, ipsilateral lung, aorta, and heart are determined and compared to those determined using the TG-43 approach. Considerable variation with source energy and differences between model-based and TG-43 doses are found for both treatment volumes and organs. Doses to the heart and aorta generally increase with increasing source energy. TG-43 underestimates the dose to the heart and aorta for all implants except those nearest to these organs where the dose is overestimated. Results suggest that model-based dose calculations are crucial for selecting prescription doses, comparing clinical endpoints, and studying radiobiological effects for permanent implant lung brachytherapy.

  3. Seed-less iodine-125 ophthalmic applicator.

    PubMed

    Puchalska, Izabela; Mielcarski, Mieczyslaw

    2003-01-01

    A method of preparation a seed-less active insert of iodine-125 ophthalmic applicator is described. Internal electrolysis was applied for fixing iodine-125 on the concave surface of the silver shell which is afterwards hermetically sealed inside a spherically shaped acrylic insert. The current-voltage characteristics of the galvanic cell used for deposition of silver iodide were determined. The results of the measurements of the energy spectra of the radiation emitted by a seed-less and seed-containing applicator are presented. The iodine-125 surface distribution uniformity on a silver shell was measured. The depth dose rate measurements indicate that the total activity incorporated in a seed-less applicator can be lower than that in seed-containing, while simultaneously assuring the desired dose rate. Copyright 2002 Elsevier Science Ltd.

  4. A permanent breast seed implant as partial breast radiation therapy for early-stage patients: A comparison of palladium-103 and iodine-125 isotopes based on radiation safety considerations

    SciTech Connect

    Keller, Brian; Sankreacha, Raxa; Rakovitch, Eileen; O'Brien, Peter; Pignol, Jean-Philippe . E-mail: Jean-Philippe.Pignol@sw.ca

    2005-06-01

    Purpose: A permanent breast seed implant (PBSI) technique has been developed as a new form of partial adjuvant radiation therapy for early-stage breast cancer. This study compares iodine-125 ({sup 125}I) and palladium-103 ({sup 103}Pd) isotopes by examining the exposure and effective dose (ED) to a patient's partner.Methods and Materials: A low-energy survey meter was used to measure exposure rates as a function of bolus thickness placed over {sup 103}Pd or {sup 125}I seeds. A general mathematical expression for the initial exposure rate at 1 m (x{sub o,1m}) from the skin surface as a function of the implant size, R, and the distance between the skin surface and the implant, d, was derived. Also, a second general equation is proposed to calculate the ED to the patient's partner.Results: The initial exposure rate at 1 meter and the ED are calculated as follows: x{sub o,1m} = (3{alpha})/2R{sup 3}{center_dot}{beta}{sup 3} [e{sup -{beta}}{sup (2R+d)}({beta}R + 1) + e{sup -{beta}}{sup {center_dot}}{sup d}({beta}R - 1)], and ED = aR{sup b} {center_dot} [e{sup -c(2R+d)} {center_dot} (cR + 1) + e{sup -cd} -bar (cR - 1)]. For {sup 125}I, the parameters are: {alpha} = 0.154409, {beta} = 0.388460, a = 197, b = -0.95, and c = 0.38846. For {sup 103}Pd, they are: {alpha} = 0.06877, {beta} = 0.421098, a = 18.6, b -0.78, and c = 0.421098. For implant diameters varying from 2 to 6 cm and skin-to-implant distances varying from 0.7 to 4 cm, the ED is consistently below 2.6 mSv using the {sup 103}Pd isotope, but more than 5 mSv in many instances and possibly up to 20 mSv using {sup 125}I.Conclusions: PBSI using {sup 103}Pd seeds appears safe because the patient's partner ED is consistently below 5 mSv. The{sup 125}I isotope is not recommended for PBSI.

  5. A permanent breast seed implant as partial breast radiation therapy for early-stage patients: a comparison of palladium-103 and iodine-125 isotopes based on radiation safety considerations.

    PubMed

    Keller, Brian; Sankreacha, Raxa; Rakovitch, Eileen; O'brien, Peter; Pignol, Jean-Philippe

    2005-06-01

    A permanent breast seed implant (PBSI) technique has been developed as a new form of partial adjuvant radiation therapy for early-stage breast cancer. This study compares iodine-125 ((125)I) and palladium-103 ((103)Pd) isotopes by examining the exposure and effective dose (ED) to a patient's partner. A low-energy survey meter was used to measure exposure rates as a function of bolus thickness placed over (103)Pd or (125)I seeds. A general mathematical expression for the initial exposure rate at 1 m (x(o,1m)) from the skin surface as a function of the implant size, R, and the distance between the skin surface and the implant, d, was derived. Also, a second general equation is proposed to calculate the ED to the patient's partner. The initial exposure rate at 1 meter and the ED are calculated as follows: x(o,1m) = 3alpha2R(3) ; ;beta(3) [e(-beta(2R+d))(betaR + 1) + e(-betad)(betaR - 1)], and ED = aR(b) [e(-c(2R+d)) (cR + 1) + e(-cd) (cR - 1)]. For (125)I, the parameters are: alpha = 0.154409, beta = 0.388460, a = 197, b = -0.95, and c = 0.38846. For (103)Pd, they are: alpha = 0.06877, beta = 0.421098, a = 18.6, b = -0.78, and c = 0.421098. For implant diameters varying from 2 to 6 cm and skin-to-implant distances varying from 0.7 to 4 cm, the ED is consistently below 2.6 mSv using the (103)Pd isotope, but more than 5 mSv in many instances and possibly up to 20 mSv using (125)I. PBSI using (103)Pd seeds appears safe because the patient's partner ED is consistently below 5 mSv. The(125)I isotope is not recommended for PBSI.

  6. Refining prostate seed brachytherapy: Comparing high-, intermediate-, and low-activity seeds for I-125 permanent seed prostate brachytherapy.

    PubMed

    Delouya, Guila; Bahary, Pascal; Carrier, Jean-François; Larouche, Renée-Xavière; Hervieux, Yannick; Béliveau-Nadeau, Dominic; Donath, David; Taussky, Daniel

    2015-01-01

    To analyze the difference in prostate coverage and dose to the rectum in men with prostate carcinoma treated with permanent seed brachytherapy with different seed activities. Forty-nine patients treated with iodine-125 permanent seed prostate brachytherapy with low-activity seeds of 0.30-0.37 mCi were identified. For each of these patients, 2 patients with similar prostate volume (±2 cc) were paired: one treated with intermediate seed activity (0.44-0.46 mCi) and one with high seed activity (0.60-0.66 mCi). The doses to prostate and rectum were compared using CT on Day 30. A total of 147 patients divided into the three seed activity groups were analyzed. Mean prostate volume was 35.7 cc (standard deviation [SD], 11.70). Compared with low-activity seeds, implants with high-activity seeds consisted of an average of 22 seeds and 4.7 needles less. The dose to the prostate (prostate volume receiving 100% of the prescribed dose [V100], prostate volume receiving 150% of the prescribed dose, and minimal dose covering 90% of the prostate volume expressed in Gy) was not higher on Day 30 (p = 0.58-0.97). The mean volume (in cubic centimeters) of rectal wall receiving 100% of the prescribed dose (V100) increased with activity: low activity, 0.34 cc (SD, 0.49), intermediate activity, 0.47 cc (SD, 0.48), and high activity, 0.72 cc (SD, 0.79) (p = 0.009). There was a trend (p = 0.073) toward a higher frequency of clinically unfavorable rectal dosimetry (V100 > 1.3 cc) in patients with high-activity seeds (16.7%) compared with low-activity (6.3%) or intermediate-activity (4.2%) seeds. High-activity seeds do not result in a higher dose to the prostate but in a higher dose to the rectum. Copyright © 2015 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  7. Fast dose kernel interpolation using Fourier transform with application to permanent prostate brachytherapy dosimetry

    SciTech Connect

    Liu, Derek Sloboda, Ron S.

    2014-05-15

    Purpose: Boyer and Mok proposed a fast calculation method employing the Fourier transform (FT), for which calculation time is independent of the number of seeds but seed placement is restricted to calculation grid points. Here an interpolation method is described enabling unrestricted seed placement while preserving the computational efficiency of the original method. Methods: The Iodine-125 seed dose kernel was sampled and selected values were modified to optimize interpolation accuracy for clinically relevant doses. For each seed, the kernel was shifted to the nearest grid point via convolution with a unit impulse, implemented in the Fourier domain. The remaining fractional shift was performed using a piecewise third-order Lagrange filter. Results: Implementation of the interpolation method greatly improved FT-based dose calculation accuracy. The dose distribution was accurate to within 2% beyond 3 mm from each seed. Isodose contours were indistinguishable from explicit TG-43 calculation. Dose-volume metric errors were negligible. Computation time for the FT interpolation method was essentially the same as Boyer's method. Conclusions: A FT interpolation method for permanent prostate brachytherapy TG-43 dose calculation was developed which expands upon Boyer's original method and enables unrestricted seed placement. The proposed method substantially improves the clinically relevant dose accuracy with negligible additional computation cost, preserving the efficiency of the original method.

  8. Iodine-125 radiation of posterior uveal melanoma

    SciTech Connect

    Packer, S.

    1987-12-01

    Twenty-eight cases of posterior choroidal melanoma were treated with iodine-125 in gold eye plaques. Eleven cases were located within 3.0 mm of the optic nerve (group A), nine were within 3.0 mm of the fovea (group B), and eight were within 3.0 mm of the optic nerve and fovea (group C). The mean follow-up of group A was 46.3 months; group B, 25.5 months; and group C, 42.7 months. Complications included macular edema, cataract and tumor growth. Visual acuity remained within two lines of that tested preoperatively for 4 of 11 patients in group A, 4 of 9 in group B, and 5 of 8 in group C. These results with iodine-125 suggest it as an appropriate treatment for patients with choroidal melanoma located near optic nerve and/or macula.

  9. Therapeutic implications of iodine-125 cytotoxicity

    SciTech Connect

    Bloomer, W.D.; McLaughlin, W.H.; Adelstein, S.J.

    1982-11-01

    The biological consequences of differential subcellular radionuclide accumulation within nuclear stuctures have important implications for the design and development of new therapeutic agents for cancer management. A growing body of experimental data demonstrates that localization of /sup 125/I within the genome results in marked cytotoxicity. Investigations of iodine-125 labeled iododeoxyuridine, DNA intercalators and tamoxifen are reviewed as representative of this new group of potential radiotherapeutic agents.

  10. Therapeutic implications of iodine-125 cytotoxicity

    SciTech Connect

    Bloomer, W.D.; McLaughlin, W.H.; Adelstein, S.J.

    1982-11-01

    The biological consequences of differential subcellular radionuclide accumulation within nuclear structures have important implications for the design and development of new therapeutic agents for cancer management. A growing body of experimental data demonstrates that localization of /sup 125/I within the genome results in marked cytotoxicity. Investigations of iodine-125 labeled iododeoxyuridine, DNA intercalators and tamoxifen are reviewed as representative of this new group of potential radiotherapeutic agents.

  11. Correlation Between Pre- and Postimplant Dosimetry for Iodine-125 Seed Implants for Localized Prostate Cancer

    SciTech Connect

    Al-Qaisieh, Bashar; Witteveen, Thelma Carey, Brendan; Henry, Ann; Bottomley, David; Smith, Jonathan; Franks, Kevin; Bownes, Peter

    2009-10-01

    Purpose: In order to evaluate implant quality for permanent prostate brachytherapy in patients with localized prostate cancer, American Brachytherapy Society and ESTRO guidelines recommend that postimplant dosimetry should be performed. To understand more about the relationship between pre- and postimplant dosimetry, a comparison was made of patients who received iodine-125 ({sup 125}I) brachytherapy between March 1995 and the end of 2004, using a preplan technique. Methods and Materials: CT postimplant dosimetry was available for 707 patients. Detailed dose volume analysis was performed using both preimplant ultrasound and postimplant CT data sets for a subgroup of 445 patients. The following parameters were compared: prostate volume covered by 100% of the prescription dose (Vp100), Vp150, and Vp200 and dose to 90% (D90) of the prostate. In addition, volume implanted (Vi) parameters were used to compare pre- and postimplant dosimetry. Vi parameters describe dose levels inside the patient, based on number of seeds, seed activity, and their spatial distribution relative to each other, without reference to the actual prostate volume or position. Results: The mean {+-} standard deviation values of preimplant (34.7 {+-} 8.9 cm{sup 3}) and postimplant (36.7 {+-} 9.4 cm{sup 3}) prostate volumes were similar. The mean ({+-}standard deviation) planned D90 was 183.4 ({+-}12.1) Gy while the D90 that was achieved was 145.5 ({+-}20.4) Gy. Over the study period, there was a steady increase of the average D90. Postimplant CT D90 and Vp100 values correlated significantly (R = 0.84; p < 0.001). The Vi and Vp parameters all showed a strong correlation. Conclusions: In this study, we showed that there is a strong correlation between transrectal ultrasound-based preimplant and CT-based postimplant dosimetry. The excellent correlation between prostate D90 and V100 values demonstrates they are both equally valid quality indices. Vi parameters are an additional measure that can be used

  12. Erectile Function Durability Following Permanent Prostate Brachytherapy

    SciTech Connect

    Taira, Al V.; Merrick, Gregory S.; Galbreath, Robert W.; Butler, Wayne M.; Wallner, Kent E.; Kurko, Brian S.; Anderson, Richard; Lief, Jonathan H.

    2009-11-01

    Purpose: To evaluate long-term changes in erectile function following prostate brachytherapy. Methods and Materials: This study included 226 patients with prostate cancer and preimplant erectile function assessed by the International Index of Erectile Function-6 (IIEF-6) who underwent brachytherapy in two prospective randomized trials between February 2001 and January 2003. Median follow-up was 6.4 years. Pre- and postbrachytherapy potency was defined as IIEF-6 >= 13 without pharmacologic or mechanical support. The relationship among clinical, treatment, and dosimetric parameters and erectile function was examined. Results: The 7-year actuarial rate of potency preservation was 55.6% with median postimplant IIEF of 22 in potent patients. Potent patients were statistically younger (p = 0.014), had a higher preimplant IIEF (p < 0.001), were less likely to be diabetic (p = 0.002), and were more likely to report nocturnal erections (p = 0.008). Potency preservation in men with baseline IIEF scores of 29-30, 24-28, 18-23, and 13-17 were 75.5% vs. 73.6%, 51.7% vs. 44.8%, 48.0% vs. 40.0%, and 23.5% vs. 23.5% in 2004 vs. 2008. In multivariate Cox regression analysis, preimplant IIEF, hypertension, diabetes, prostate size, and brachytherapy dose to proximal penis strongly predicted for potency preservation. Impact of proximal penile dose was most pronounced for men with IIEF of 18-23 and aged 60-69. A significant minority of men who developed postimplant impotence ultimately regained erectile function. Conclusion: Potency preservation and median IIEF scores following brachytherapy are durable. Thoughtful dose sparing of proximal penile structures and early penile rehabilitation may further improve these results.

  13. Myths and fallacies in permanent prostate brachytherapy

    SciTech Connect

    Butler, Wayne M.; Merrick, Gregory S

    2003-09-30

    Because there are competing modalities to treat early-stage prostate cancer, the constraints or deficiencies of one modality may be erroneously applied to others. Some valid concerns arising from surgery and external beam therapy, which have been falsely transferred to brachytherapy, are constraints based on patient age, clinical and pathological parameters, patient weight, and size of prostate. Although the constraints have a valid basis in one modality, knowledge of the origin and mechanism of the constraint has provided a means to circumvent or overcome it in brachytherapy. Failures as measured by biochemical no-evidence of disease (bNED) survival may be attributed to extracapsular disease extension. Such extension often expresses itself in surrogate parameters such as a high percentage of positive biopsies, perineural invasion, or the dominant pattern in Gleason score histology. Failures due to such factors may be prevented by implanting with consistent extracapsular dosimetric margins. Some presumed limitations on prostate brachytherapy originated from data on patients implanted in the first few years the procedure was being developed. Most of the urinary morbidity and a significant part of the decrease in sexual function observed may be avoided by controlling the dosimetry along the prostatic and membranous urethra and at the penile bulb.

  14. American Brachytherapy Society (ABS) recommendations for transperineal permanent brachytherapy of prostate cancer.

    PubMed

    Nag, S; Beyer, D; Friedland, J; Grimm, P; Nath, R

    1999-07-01

    To develop and disseminate the American Brachytherapy Society (ABS) recommendations for the clinical quality assurance and guidelines of permanent transperineal prostate brachytherapy with 125I or 103Pd. The ABS formed a committee of experts in prostate brachytherapy to develop consensus guidelines through a critical analysis of published data supplemented by their clinical experience. The recommendations of the panels were reviewed and approved by the Board of Directors of the ABS. Patients with high probability of organ-confined disease are appropriately treated with brachytherapy alone. Brachytherapy candidates with a significant risk of extraprostatic extension should be treated with supplemental external beam radiation therapy (EBRT). Patient selection guidelines were developed. Dosimetric planning of the implant should be carried out for all patients before seed insertion. A modified peripheral loading is preferred. The AAPM TG-43 recommendations requiring a change in prescription dose for 125I sources should be universally implemented. The recommended prescription doses for monotherapy are 145 Gy for 125I and 115-120 Gy for 103Pd. The corresponding boost doses (after 40-50 Gy EBRT) are 100-110 Gy and 80-90 Gy, respectively. Clinical evidence to guide selection of radionuclide (103Pd or 125I) is lacking. Post implant dosimetry and evaluation must be performed on all patients. It is suggested that the dose that covers 90% (D90) and 100% (D100) of the prostate volume and the percentage of the prostate volume receiving the prescribed dose (V100) be obtained from a dose-volume histogram (DVH) and reported. Guidelines for appropriate patient selection, dose reporting, and improved quality of permanent prostate brachytherapy are presented. These broad recommendations are intended to be technical and advisory in nature, but the ultimate responsibility for the medical decisions rests with the treating physician. This is a constantly evolving field, and the

  15. Brachytherapy

    MedlinePlus

    ... care for brachytherapy catheters. top of page What equipment is used? For permanent implants, radioactive material (which ... the tumor. top of page Who operates the equipment? The equipment is operated by a medical physicist, ...

  16. The effect of obesity on rectal dosimetry after permanent prostate brachytherapy.

    PubMed

    Patil, Nikhilesh; Crook, Juanita; Saibishkumar, Elantholi P; Aneja, Manipdip; Borg, Jette; Pond, Greg; Ma, Clement

    2009-01-01

    Men with higher body mass index (BMI) tend to have more fatty tissue in prostate-rectum interface, which may reduce the rectal wall dose by the inverse square law. We hypothesized that men with higher BMI will have a lower dose to the rectal wall and less rectal toxicity after permanent prostate implant. Prospectively collected data on rectal dosimetry/toxicity and BMI of 407 patients who underwent iodine-125 ((125)I) prostate implant were analyzed. Postimplant dosimetry used CT-MRI fusion on Day 30. Rectal wall was contoured on all slices where seeds were seen. The volume of rectal wall receiving the prescribed dose (RV(100) in cm(3)) and the dose to 1cc of rectal wall (RD(1cc)) were reported. Other factors evaluated for association with rectal dosimetry and toxicity included age, diabetes, hypertension, smoking, use of neoadjuvant hormones, T stage, baseline prostate volume, 1 month prostate edema, seed type and activity, and prostate dosimetry factors (the isodose enclosing 90% of the prostate volume [D(90)], the percentage of the prostate volume enclosed by the prescription [V(100)], and the percentage of the prostate volume enclosed by the 150% isodose [V(150)]). Rectal toxicity was reported as per Radiation Therapy Oncology Group criteria. BMIs ranged from 15.9 to 46.8 (mean+/-standard deviation [SD]: 27.8+/-4.2). The mean+/-SD values for RV(100) and RD(1cc) were 0.79+/-0.49cm(3) and 128.2+/-27.8Gy, respectively. There was a significant negative association of BMI with RV(100) (p=0.007) and RD(1cc) (p=0.01) on univariate analysis. The mean RV(100) and RD(1cc) for men with higher BMI (>27.8) were lower compared with their slimmer counterparts (0.70 vs. 0.86cm(3) and 123.4 vs. 132.4Gy, respectively). On multivariate analysis for RV(100) and RD(1cc), BMI remained significant (p-values 0.004 and 0.01, respectively) along with prostate volume and V(150), suggesting that anatomic factors are important in rectal dosimetry in prostate brachytherapy. Overall the

  17. ACR appropriateness criteria: Permanent source brachytherapy for prostate cancer.

    PubMed

    Davis, Brian J; Taira, Al V; Nguyen, Paul L; Assimos, Dean G; D'Amico, Anthony V; Gottschalk, Alexander R; Gustafson, Gary S; Keole, Sameer R; Liauw, Stanley L; Lloyd, Shane; McLaughlin, Patrick W; Movsas, Benjamin; Prestidge, Bradley R; Showalter, Timothy N; Vapiwala, Neha

    To provide updated American College of Radiology (ACR) appropriateness criteria for transrectal ultrasound-guided transperineal interstitial permanent source brachytherapy. The ACR appropriateness criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 3 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment. Permanent prostate brachytherapy (PPB) is a treatment option for appropriately selected patients with localized prostate cancer with low to very high risk disease. PPB monotherapy remains an appropriate and effective curative treatment for low-risk prostate cancer patients demonstrating excellent long-term cancer control and acceptable morbidity. PPB monotherapy can be considered for select intermediate-risk patients with multiparametric MRI useful in evaluation of such patients. High-risk patients treated with PPB should receive supplemental external beam radiotherapy (EBRT) along with androgen deprivation. Similarly, patients with involved pelvic lymph nodes may also be considered for such combined treatment but reported long-term outcomes are limited. Computed tomography-based postimplant dosimetry completed within 60 days of PPB is essential for quality assurance. PPB may be considered for treatment of local recurrence after EBRT but is associated with an increased risk of toxicity. Updated appropriateness criteria for patient evaluation, selection, treatment, and postimplant dosimetry are given. These criteria are intended to be advisory only with the final responsibility for patient care residing with the treating

  18. Comparison of biochemical failure definitions for permanent prostate brachytherapy

    SciTech Connect

    Kuban, Deborah A. . E-mail: dakuban@mdanderson.org; Levy, Larry B.; Potters, Louis; Beyer, David C.; Blasko, John C.; Moran, Brian J.; Ciezki, Jay P.; Zietman, Anthony L.; Zelefsky, Michael J.; Pisansky, Thomas M.; Elshaikh, Mohamed; Horwitz, Eric M.

    2006-08-01

    Purpose: To assess prostate-specific antigen (PSA) failure definitions for patients with Stage T1-T2 prostate cancer treated by permanent prostate brachytherapy. Methods and Materials: A total of 2,693 patients treated with radioisotopic implant as solitary treatment for T1-T2 prostatic adenocarcinoma were studied. All patients had a pretreatment PSA, were treated at least 5 years before analysis, 1988 to 1998, and did not receive hormonal therapy before recurrence. Multiple PSA failure definitions were tested for their ability to predict clinical failure. Results: Definitions which determined failure by a certain increment of PSA rise above the lowest PSA level to date (nadir + x ng/mL) were more sensitive and specific than failure definitions based on PSA doubling time or a certain number of PSA rises. The sensitivity and specificity for the nadir + 2 definition were 72% and 83%, vs. 51% and 81% for 3 PSA rises. The surgical type definitions (PSA exceeding an absolute value) could match this sensitivity and specificity but only when failure was defined as exceeding a PSA level in the 1-3 ng/mL range and only when patients were allowed adequate time to nadir. When failure definitions were compared by time varying covariate regression analysis, nadir + 2 ng/mL retained the best fit. Conclusions: For patients treated by permanent radioisotopic implant for prostate cancer, the definition nadir + 2 ng/mL provides the best surrogate for failure throughout the entire follow-up period, similar to patients treated by external beam radiotherapy. Therefore, the same PSA failure definition could be used for both modalities. For brachytherapy patients with long-term follow-up, at least 6 years, defining failure as exceeding an absolute PSA level in the 0.5 ng/mL range may be reasonable.

  19. American Brachytherapy Society consensus guidelines for transrectal ultrasound-guided permanent prostate brachytherapy.

    PubMed

    Davis, Brian J; Horwitz, Eric M; Lee, W Robert; Crook, Juanita M; Stock, Richard G; Merrick, Gregory S; Butler, Wayne M; Grimm, Peter D; Stone, Nelson N; Potters, Louis; Zietman, Anthony L; Zelefsky, Michael J

    2012-01-01

    To provide updated American Brachytherapy Society (ABS) guidelines for transrectal ultrasound-guided transperineal interstitial permanent prostate brachytherapy (PPB). The ABS formed a committee of brachytherapists and researchers experienced in the clinical practice of PPB to formulate updated guidelines for this technique. Sources of input for these guidelines included prior published guidelines, clinical trials, published literature, and experience of the committee. The recommendations of the committee were reviewed and approved by the Board of Directors of the ABS. Patients with high probability of organ-confined disease or limited extraprostatic extension are considered appropriate candidates for PPB monotherapy. Low-risk patients may be treated with PPB alone without the need for supplemental external beam radiotherapy. High-risk patients should receive supplemental external beam radiotherapy if PPB is used. Intermediate-risk patients should be considered on an individual case basis. Intermediate-risk patients with favorable features may appropriately be treated with PPB monotherapy but results from confirmatory clinical trials are pending. Computed tomography-based postimplant dosimetry performed within 60 days of the implant is considered essential for maintenance of a satisfactory quality assurance program. Postimplant computed tomography-magnetic resonance image fusion is viewed as useful, but not mandatory. Updated guidelines for patient selection, workup, treatment, postimplant dosimetry, and followup are provided. These recommendations are intended to be advisory in nature with the ultimate responsibility for the care of the patients resting with the treating physicians. Copyright © 2012. Published by Elsevier Inc.

  20. Primary Causes of Death After Permanent Prostate Brachytherapy

    SciTech Connect

    Bittner, Nathan; Merrick, Gregory S. Galbreath, Robert W.; Butler, Wayne M.; Wallner, Kent E.; Allen, Zachariah A.; Brammer, Sarah G.; Moyad, Mark

    2008-10-01

    Purpose: To evaluate the primary causes of death in low-risk (low-risk), intermediate-risk (intermediate-risk), and high-risk (high-risk) patients undergoing permanent prostate brachytherapy with or without supplemental therapies. Methods and Materials: From April 1995 through November 2004, a total of 1,354 consecutive patients underwent prostate brachytherapy. All patients underwent brachytherapy >3 years before analysis. Of the patients, 532 (39.3%) received androgen deprivation therapy and 703 (51.9%) received supplemental radiation therapy. The median follow-up was 5.4 years. Multiple parameters were evaluated as predictors of cause-specific, biochemical progression-free, and overall survival. Results: The 10-year cause-specific survival was 97.0% (99.7%, 99.0%, and 90.1% for low-risk, intermediate-risk, and high-risk patients). Overall survival was 76.7% (82.5%, 78.3%, and 67.6% for low-, intermediate-, and high-risk patients, respectively). The cumulative death rate for cardiovascular disease was 11.5% (8.7%, 9.3%, and 19.8% for low-, intermediate-, and high-risk patients). The death rate from second malignancies (nonprostate cancer) was 7.2% and was not substantially different when stratified by risk group. Death from all other causes was 6.5% for the entire cohort but 1.3%, 5.0%, and 10.8% for low-, intermediate-, and high-risk patients. In multivariate analysis, death from prostate cancer was best predicted by Gleason score and risk group, whereas death from cardiovascular disease, nonprostate cancer, and all other causes were most closely related to patient age and tobacco use. Conclusions: Although cardiovascular mortality was the predominant cause of death, prostate cancer was responsible for approximately 10% of all deaths. In particular, overall survival was poorest in the high-risk group. Although high-risk patients were most likely to die of prostate cancer, the divergence in overall survival between high-risk and lower-risk patients primarily

  1. Segmental Urethral Dosimetry and Urinary Toxicity in Patients With No Urinary Symptoms Before Permanent Prostate Brachytherapy

    SciTech Connect

    Thomas, Carys; Keyes, Mira Liu, Mitchell; Moravan, Veronika

    2008-10-01

    Purpose: To determine whether segmental urethral dosimetry is predictive for the degree of urinary morbidity after prostate brachytherapy in patients with no urinary symptoms before prostate brachytherapy. Methods and Materials: Between May 2000 and November 2005, 1,107 patients underwent iodine-125 monotherapy with urethral sparing techniques. A total of 166 patients fulfilled the selection criteria: baseline (International Prostate Symptom Score) IPSS {<=}5, no androgen deprivation therapy, and prostate ultrasound planning volumes (PUTV) <45 mL. The median follow-up was 44 months. Urinary morbidity was defined by maximum increase in IPSS, time to IPSS resolution, maximum Radiation Therapy Oncology Group (RTOG) score, time to RTOG resolution, and urinary retention. Surrogate deviated urethra was contoured and doses calculated at the base, mid-prostate, apex, and urogenital diaphragm. Univariate and multivariate analysis was used to evaluate urethral and prostate dosimetry, age, PUTV, and number of needles for their association with urinary morbidity. Results: Urethral dose was fairly constant in all urethra segments except prostate base, where the variation in does was large. On multivariate analysis, higher urethral base D50, V100, and larger PUTV were predictive for higher maximum increase in IPSS. Higher urethral base V100 and larger PUTV predicted for prolonged IPSS resolution. Higher urethral base D50 and larger needle number predicted for longer RTOG resolution. Higher urethral base V100 predicted for RTOG {>=}2 toxicity. Conclusions: Radiation dose to the urethral base, larger PUTV, and needle number, predicted for increased urinary toxicity after prostate brachytherapy. Correlation between urinary morbidity and urethral base dosimetry may reflect a large variation in urethral dose observed at the prostate base.

  2. Long-Term Results of an RTOG Phase II Trial (00-19) of External-Beam Radiation Therapy Combined With Permanent Source Brachytherapy for Intermediate-Risk Clinically Localized Adenocarcinoma of the Prostate

    SciTech Connect

    Lawton, Colleen A.; Yan, Yan; Lee, W. Robert; Gillin, Michael; Firat, Selim; Baikadi, Madhava; Crook, Juanita; Kuettel, Michael; Morton, Gerald; Sandler, Howard

    2012-04-01

    Purpose: External-beam radiation therapy combined with low-doserate permanent brachytherapy are commonly used to treat men with localized prostate cancer. This Phase II trial was performed to document late gastrointestinal or genitourinary toxicity as well as biochemical control for this treatment in a multi-institutional cooperative group setting. This report defines the long-term results of this trial. Methods and Materials: All eligible patients received external-beam radiation (45 Gy in 25 fractions) followed 2-6 weeks later by a permanent iodine 125 implant of 108 Gy. Late toxicity was defined by the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer late radiation morbidity scoring scheme. Biochemical control was defined by the American Society for Therapeutic Radiology and Oncology (ASTRO) Consensus definition and the ASTRO Phoenix definition. Results: One hundred thirty-eight patients were enrolled from 20 institutions, and 131 were eligible. Median follow-up (living patients) was 8.2 years (range, 2.7-9.3 years). The 8-year estimate of late grade >3 genitourinary and/or gastrointestinal toxicity was 15%. The most common grade >3 toxicities were urinary frequency, dysuria, and proctitis. There were two grade 4 toxicities, both bladder necrosis, and no grade 5 toxicities. In addition, 42% of patients complained of grade 3 impotence (no erections) at 8 years. The 8-year estimate of biochemical failure was 18% and 21% by the Phoenix and ASTRO consensus definitions, respectively. Conclusion: Biochemical control for this treatment seems durable with 8 years of follow-up and is similar to high-dose external beam radiation alone or brachytherapy alone. Late toxicity in this multi-institutional trial is higher than reports from similar cohorts of patients treated with high-dose external-beam radiation alone or permanent low-doserate brachytherapy alone, perhaps suggesting further attention to strategies that limit doses to

  3. Relationship between two year PSA nadir and biochemical recurrence in prostate cancer patients treated with iodine-125 brachytherap*

    PubMed Central

    Franca, Carlos Antônio da Silva; Vieira, Sérgio Lannes; Carvalho, Antonio Carlos Pires; Bernabe, Antonio Jose Serrano; Penna, Antonio Belmiro Rodrigues Campbell

    2014-01-01

    Objective To evaluate the relationship between two year PSA nadir (PSAn) after brachytherapy and biochemical recurrence rates in prostate cancer patients. Materials and Methods In the period from January 1998 to August 2007, 120 patients were treated with iodine-125 brachytherapy alone. The results analysis was based on the definition of biochemical recurrence according to the Phoenix Consensus. Results Biochemical control was observed in 86 patients (71.7%), and biochemical recurrence, in 34 (28.3%). Mean PSAn was 0.53 ng/ml. The mean follow-up was 98 months. The patients were divided into two groups: group 1, with two year PSAn < 0.5 ng/ml after brachytherapy (74 patients; 61.7%), and group 2, with two year PSAn ≥ 0.5 ng/ml after brachytherapy (46 patients; 38.3%). Group 1 presented biochemical recurrence in 15 patients (20.3%), and group 2, in 19 patients (43.2%) (p < 0.02). The analysis of biochemical disease-free survival at seven years, stratified by the two groups, showed values of 80% and 64% (p < 0.02), respectively. Conclusion Levels of two year PSAn ≥ 0.5 ng/ml after brachytherapy are strongly correlated with a poor prognosis. This fact may help to identify patients at risk for disease recurrence. PMID:25741055

  4. Urethral toxicity after LDR brachytherapy: experience in Japan.

    PubMed

    Tanaka, Nobumichi; Asakawa, Isao; Hasegawa, Masatoshi; Fujimoto, Kiyohide

    2015-01-01

    Urinary toxicity is common after low-dose-rate (LDR) brachytherapy, and the resolution of urinary toxicity is a concern. In particular, urinary frequency is the most common adverse event among the urinary toxicities. We have previously reported that approximately 70% of patients experience urinary frequency during the first 6 months after seed implantation. Most urinary adverse events were classified as Grade 1, and Grade 2 or higher adverse events were rare. The incidence of urinary retention was approximately 2-4%. A high International Prostate Symptom Score before seed implantation was an independent predictor of acute urinary toxicity of Grade 2 or higher. Several previous reports from the United States also supported this trend. In Japan, LDR brachytherapy was legally approved in 2003. A nationwide prospective cohort study entitled Japanese Prostate Cancer Outcome Study of Permanent Iodine-125 Seed Implantation was initiated in July 2005. It is an important issue to limit urinary toxicities in patients who undergo LDR brachytherapy.

  5. Interstitial iodine-125 implant in the management of unresectable pancreatic carcinoma

    SciTech Connect

    Syed, A.M.; Puthawala, A.A.; Neblett, D.L.

    1983-09-01

    Eighteen patients with locally advanced adenocarcinoma of the head, body and tail of the pancreas were treated by a combination of biliary bypass, external and interstitial irradiation at Southern California Cancer Center of California Hospital Medical Center, Los Angeles, and Memorial Hospital Medical Center of Long Beach, Long Beach, CA, from July 31, 1975 to December 31, 1980. A dose of 3000 to 5000 rad was delivered to the pancreas and regional lymph nodes by external irradiation utilizing megavoltage units and 10,000 to 15,000 rad to the pancreas and metastatic lymph nodes by permanent Iodine-125 implants. In this group of 18 patients with unresectable carcinoma of the pancreas, excellent palliation of pain, jaundice and vomiting was achieved, with a median survival of 14 months.

  6. Determination of the prescription dose for biradionuclide permanent prostate brachytherapy.

    PubMed

    Nuttens, V E; Lucas, S

    2008-12-01

    A model based on the linear quadratic model that has been corrected for repopulation, sublethal cell damage repair, and RBE effect has been used to determine the prescription dose for prostate permanent brachytherapy using seeds loaded with a mixture of 103Pd and 125I or a mixture of 103Pd and 131Cs. The prescription dose was determined by comparing the tumor cell survival fractions between the considered biradionuclide seed implant and one monoradionuclide seed implant chosen from 103Pd, 125I, and 131Cs. Prostate edema is included in the model. The influence of the value of the radiobiological parameters and RBE were also investigated. Two mixtures of radionuclides were considered: 103Pd0.75-125I0.25 and 103Pd0.25-131Cs0.75, where the subscripts indicate the fractions of total initial internal activity in the biradionuclide seed. These fractions were selected in order to obtain a dose distribution that lies between that of 103Pd and 125I/131Cs. As expected, the computed prescription dose values are dependent on the model parameters (edema half-life and magnitude, radiobiogical parameters, and RBE). The radionuclide used as a benchmark also has a strong impact on the derived prescribed dose. The large uncertainties in the radiobiological parameters and RBE values produce big errors in the computed prescribed dose. Averaged over the range of all the parameters and depending on the radionuclide used as a benchmark (in subscript), the derived prescription dose for the first mixture (PdI) would be: D(PdI)(Pd)=142(+15)(-16) Gy and D(PdI)(I)=142(+6)(-8) Gy; and D(PdCs)(Pd)=128(+13)(-13) Gy and D(PdCs)(Cs)=115(+6)(-7) Gy for the PdCs mixture. The uncertainties could be reduced if the radiobiological parameters and RBE value were known more accurately. However, as edema characteristics are patient dependent and can be obtained only after the treatment, an unpredictable error is unavoidable.

  7. Determination of the prescription dose for biradionuclide permanent prostate brachytherapy

    SciTech Connect

    Nuttens, V. E.; Lucas, S.

    2008-12-15

    A model based on the linear quadratic model that has been corrected for repopulation, sublethal cell damage repair, and RBE effect has been used to determine the prescription dose for prostate permanent brachytherapy using seeds loaded with a mixture of {sup 103}Pd and {sup 125}I or a mixture of {sup 103}Pd and {sup 131}Cs. The prescription dose was determined by comparing the tumor cell survival fractions between the considered biradionuclide seed implant and one monoradionuclide seed implant chosen from {sup 103}Pd, {sup 125}I, and {sup 131}Cs. Prostate edema is included in the model. The influence of the value of the radiobiological parameters and RBE were also investigated. Two mixtures of radionuclides were considered: {sup 103}Pd{sub 0.75}-{sup 125}I{sub 0.25} and {sup 103}Pd{sub 0.25}-{sup 131}Cs{sub 0.75}, where the subscripts indicate the fractions of total initial internal activity in the biradionuclide seed. These fractions were selected in order to obtain a dose distribution that lies between that of {sup 103}Pd and {sup 125}I/{sup 131}Cs. As expected, the computed prescription dose values are dependent on the model parameters (edema half-life and magnitude, radiobiogical parameters, and RBE). The radionuclide used as a benchmark also has a strong impact on the derived prescribed dose. The large uncertainties in the radiobiological parameters and RBE values produce big errors in the computed prescribed dose. Averaged over the range of all the parameters and depending on the radionuclide used as a benchmark (in subscript), the derived prescription dose for the first mixture (PdI) would be: D{sub Pd}{sup PdI}=142{sub -16}{sup +15} Gy and D{sub I}{sup PdI}=142{sub -8}{sup +6} Gy; and D{sub Pd}{sup PdCs}=128{sub -13}{sup +13} Gy and D{sub Cs}{sup PdCs}=115{sub -7}{sup +6} Gy for the PdCs mixture. The uncertainties could be reduced if the radiobiological parameters and RBE value were known more accurately. However, as edema characteristics are patient

  8. Partial breast brachytherapy

    MedlinePlus

    ... brachytherapy; Accelerated partial breast irradiation - brachytherapy; Partial breast radiation therapy - brachytherapy; Permanent breast seed implant; PBSI; Low-dose radiotherapy - breast; High-dose radiotherapy - breast; Electronic balloon ...

  9. Primary Gleason Grade 4 Impact on Biochemical Recurrence After Permanent Interstitial Brachytherapy in Japanese Patients With Low- or Intermediate-Risk Prostate Cancer

    SciTech Connect

    Uesugi, Tatsuya; Saika, Takashi; Edamura, Kohei; Nose, Hiroyuki; Kobuke, Makoto; Ebara, Shin; Abarzua, Fernand; Katayama, Norihisa; Yanai, Hiroyuki; Nasu, Yasutomo; Kumon, Hiromi

    2012-02-01

    Purpose: To reveal a predictive factor for biochemical recurrence (BCR) after permanent prostate brachytherapy (PPB) using iodine-125 seed implantation in patients with localized prostate cancer classified as low or intermediate risk based on National Comprehensive Cancer Network (NCCN) guidelines. Methods and Materials: From January 2004 to December 2009, 414 consecutive Japanese patients with clinically localized prostate cancer classified as low or intermediate risk based on the NCCN guidelines were treated with PPB. The clinical factors including pathological data reviewed by a central pathologist and follow-up data were prospectively collected. Kaplan-Meier and Cox regression analyses were used to assess the factors associated with BCR. Results: Median follow-up was 36.5 months. The 2-, 3-, 4-, and 5-year BCR-free rates using the Phoenix definition were 98.3%, 96.0%, 91.6%, and 87.0%, respectively. On univariate analysis, the Gleason score, especially primary Gleason grade 4 in biopsy specimens, was a strong predicting factor (p < 0.0001), while age, initial prostate-specific antigen (PSA) level, T stage, and minimal dose delivered to 90% of the prostate volume (D90) were insignificant. Multivariate analysis indicated that a primary Gleason grade 4 was the most powerful prognostic factor associated with BCR (hazard ratio = 6.576, 95% confidence interval, 2.597-16.468, p < 0.0001). Conclusions: A primary Gleason grade 4 carried a worse BCR prognosis than the primary grade 3 in patients treated with PPB. Therefore, the indication for PPB in patients with a Gleason sum of 4 + 3 deserves careful and thoughtful consideration.

  10. [Experience of brachytherapy using I-125 seed permanent implants for localized prostate cancer].

    PubMed

    Toya, Kazuhito; Yorozu, Atsunori; Ohashi, Toshio; Okada, Masahiro; Itoh, Reiko; Monma, Tetsuo; Saito, Shiro; Fukada, Junichi; Sugawara, Akitomo; Dokiya, Takushi

    2005-10-01

    We report here our experience of brachytherapy using I-125 seeds for localized prostate cancer in 100 patients. We carried out brachytherapy with I-125 seed permanent implants in 100 patients with localized prostate cancer between September 2003 and October 2004. Preplanning dosimetry was done using transrectal ultrasonic images obtained three or four weeks prior to treatment. Using transrectal ultrasound, we inserted I-125 seeds in the prostate through needles according to the preplanning diagram. We then examined the results on prostate CT performed one month later. It was necessary to describe transrectal ultrasonic image such as preplanning. There were several cases in which the source arrangement of the schedule was corrected immediately before the operation. In the examination after one month, the numerical value at the start of treatment initially was not satisfactory, but we eventually obtained a result that could to be evaluated. We carried out permanent implant brachytherapy for localized prostate cancer using I-125 seeds and reported our experience.

  11. 78 FR 41125 - Interim Enforcement Policy for Permanent Implant Brachytherapy Medical Event Reporting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-09

    ... COMMISSION Interim Enforcement Policy for Permanent Implant Brachytherapy Medical Event Reporting AGENCY... discretion for certain violations of regulations for reporting medical events occurring under an NRC licensee...: Background In SECY-05-0234, ``Adequacy of Medical Event Definitions in 10 CFR 35.3045, and...

  12. Alternative Dose for Choroidal Melanoma Treated With an Iodine-125 Radioactive Plaque: A Single-Institution Retrospective Study

    SciTech Connect

    Saconn, Paul A.; Gee, Christopher J.; Greven, Craig M.; McCoy, Thomas P.; Ekstrand, Kenneth E.; Greven, Kathryn M.

    2010-11-01

    Purpose: The Collaborative Ocular Melanoma Study (COMS) established iodine-125 plaque brachytherapy as an accepted standard treatment for medium-size choroidal melanoma. In the COMS, the prescription dose was 85 Gy. This is a retrospective review of our outcomes in patients treated with lower doses than those used in the COMS. Methods and Materials: From 1990 to 2004, 62 patients were treated with iodine-125 plaque brachytherapy for choroidal melanoma. COMS eye plaques were used with dose prescribed to the apex of the tumor. The median and average dose rates at the tumor apex were 63.5 cGy/h and 62.7 cGy/h, respectively. The median and average total doses were 63.0 Gy and 62.5 Gy (range, 56-69 Gy), respectively. The median and mean durations of implant were 100.0 hours and 101.1 hours (range, 71-165 hours). Results: Median follow-up time was 58.2 months. The 5-year outcomes including overall survival, disease-free survival, cause-specific survival, local failure, secondary enucleation rate, and visual acuity (VA) <20/200 were estimated using the Kaplan-Meier method. Overall, there were 7 local failures, 4 distant failures, and 10 secondary enucleations (6 due to local failure and 4 due to treatment complications). Univariate analysis was performed to identify significant prognostic factors associated with disease-free survival (baseline VA in tumor eye, tumor shape), cause-specific survival (diabetic retinopathy), local failure (none found), secondary enucleation rate (diabetic retinopathy, basal tumor dimension) and VA <20/200 (diabetic retinopathy, tumor shape, age, retinal detachment, treatment depth, and history of vision-limiting condition). Conclusions: Our survival and local control outcomes are comparable to those of the COMS. However, VA at 5 years seems to be better. Lower doses of radiation could potentially lead to better visual outcomes.

  13. Iodine-125 Seeds Strand for Treatment of Tumor Thrombus in Inferior Vena Cava: An Experimental Study in a Rabbit Model

    SciTech Connect

    Zhang, Wen Yan, Zhiping Luo, Jianjun Fang, Zhuting Wu, Linlin Liu, QingXin Qu, Xudong Liu, Lingxiao Wang, Jianhua

    2013-10-15

    Objective: The purpose of this study was to establish an animal model of implanted inferior vena cava tumor thrombus (IVCTT) and to evaluate the effect of linear iodine-125 seeds strand in treating implanted IVCTT. Methods: Tumor cell line VX{sub 2} was inoculated subcutaneously into New Zealand rabbit to develop the parent tumor. The tumor strip was inoculated into inferior vena cava (IVC) to establish the IVCTT model. The IVCTT was confirmed by multidetector computed tomography (MDCT) after 2 weeks. Twelve rabbits with IVCTT were randomly divided into two groups. Treatment group (group T; n = 6) underwent Iodine-125 seeds brachytherapy, and the control group (group C; n = 6) underwent blank seeds strand. The blood laboratory examination (including blood routine examination, hepatic and renal function), body weight, survival time, and IVCTT volume by MDCT were monitored. All rabbits were dissected postmortem, and the therapeutic effects were evaluated on the basis of histopathology. The proliferating cell nuclear antigen index (PI) and apoptosis index (AI) of IVCTT were compared between two groups. T test, Wilcoxon rank test, and Kaplan-Meier survival curve analysis were used. Results: The success rate of establishing IVCTT was 100 %. The body weight loss and cachexia of rabbits in group C appeared earlier than in group T. Body weight in the third week, the mean survival time, PI, AI in groups T and C were 2.23 {+-} 0.12 kg, 57.83 {+-} 8.68 days, (16.73 {+-} 5.18 %), (29.47 {+-} 7.18 %), and 2.03 {+-} 0.13 kg, 43.67 {+-} 5.28 days, (63.01 {+-} 2.01 %), (6.02 {+-} 2.93 %), respectively. There were statistically significant differences between group T and group C (P < 0.05). The IVCTT volume of group T was remarkably smaller than that of group C. Conclusions: Injecting and suspensory fixing VX2 tumor strip into IVC is a reliable method to establish IVCTT animal model. The linear Iodine-125 seeds strand brachytherapy was a safe and effective method for treating IVCTT

  14. SU-E-T-259: Particle Swarm Optimization in Radial Dose Function Fitting for a Novel Iodine-125 Seed

    SciTech Connect

    Wu, X; Duan, J; Popple, R; Huang, M; Shen, S; Brezovich, I; Cardan, R; Benhabib, S

    2014-06-01

    Purpose: To determine the coefficients of bi- and tri-exponential functions for the best fit of radial dose functions of the new iodine brachytherapy source: Iodine-125 Seed AgX-100. Methods: The particle swarm optimization (PSO) method was used to search for the coefficients of the biand tri-exponential functions that yield the best fit to data published for a few selected radial distances from the source. The coefficients were encoded into particles, and these particles move through the search space by following their local and global best-known positions. In each generation, particles were evaluated through their fitness function and their positions were changed through their velocities. This procedure was repeated until the convergence criterion was met or the maximum generation was reached. All best particles were found in less than 1,500 generations. Results: For the I-125 seed AgX-100 considered as a point source, the maximum deviation from the published data is less than 2.9% for bi-exponential fitting function and 0.2% for tri-exponential fitting function. For its line source, the maximum deviation is less than 1.1% for bi-exponential fitting function and 0.08% for tri-exponential fitting function. Conclusion: PSO is a powerful method in searching coefficients for bi-exponential and tri-exponential fitting functions. The bi- and tri-exponential models of Iodine-125 seed AgX-100 point and line sources obtained with PSO optimization provide accurate analytical forms of the radial dose function. The tri-exponential fitting function is more accurate than the bi-exponential function.

  15. Ejaculatory Function After Permanent {sup 125}I Prostate Brachytherapy for Localized Prostate Cancer

    SciTech Connect

    Huyghe, Eric Delannes, Martine; Wagner, Fabien M.; Delaunay, Boris; Nohra, Joe; Thoulouzan, Matthieu; Shut-Yee, J. Yeung; Plante, Pierre; Soulie, Michel; Thonneau, Patrick; Bachaud, Jean Marc

    2009-05-01

    Purpose: Ejaculatory function is an underreported aspect of male sexuality in men treated for prostate cancer. We conducted the first detailed analysis of ejaculatory function in patients treated with permanent {sup 125}I prostate brachytherapy for localized prostate cancer. Patients and Methods: Of 270 sexually active men with localized prostate cancer treated with permanent {sup 125}I prostate brachytherapy, 241 (89%), with a mean age of 65 years (range, 43-80), responded to a mailed questionnaire derived from the Male Sexual Health Questionnaire regarding ejaculatory function. Five aspects of ejaculatory function were examined: frequency, volume, dry ejaculation, pleasure, and pain. Results: Of the 241 sexually active men, 81.3% had conserved ejaculatory function after prostate brachytherapy; however, the number of patients with rare/absent ejaculatory function was double the pretreatment number (p < .0001). The latter finding was correlated with age (p < .001) and the preimplant International Index of Erectile Function score (p < .001). However, 84.9% of patients with maintained ejaculatory function after implantation reported a reduced volume of ejaculate compared with 26.9% before (p < .001), with dry ejaculation accounting for 18.7% of these cases. After treatment, 30.3% of the patients experienced painful ejaculation compared with 12.9% before (p = .0001), and this was associated with a greater number of implanted needles (p = .021) and the existence of painful ejaculation before implantation (p < .0001). After implantation, 10% of patients who continued to be sexually active experienced no orgasm compared with only 1% before treatment. in addition, more patients experienced late/difficult or weak orgasms (p = .001). Conclusion: Most men treated with brachytherapy have conserved ejaculatory function after prostate brachytherapy. However, most of these men experience a reduction in volume and a deterioration in orgasm.

  16. Comparison of 3 different postimplant dosimetry methods following permanent {sup 125}I prostate seed brachytherapy

    SciTech Connect

    Marcu, Loredana G.; Gowda, Raghu

    2013-10-01

    Postimplant dosimetry (PID) after Iodine-125 ({sup 125}I) implant of the prostate should offer a reliable qualitative assessment. So far, there is no consensus regarding the optimum PID method, though the latest literature is in favor of magnetic resonance imaging (MRI). This study aims to simultaneously compare 3 PID techniques: (1) MRI-computed tomography (CT) fusion; (2) ultrasound (US)-CT fusion; and (3) manual target delineation on CT. The study comprised 10 patients with prostate cancer. CT/MR scans with urinary catheters in place for PID were done either on day 0 or day 1 postimplantation. The main parameter evaluated and compared among methods was target D90. The results show that CT-based D90s are lower than US-CT D90s (median difference,−6.85%), whereas MR-CT PID gives higher D90 than US-CT PID (median difference, 4.25%). Manual contouring on CT images tends to overestimate the prostate volume compared with transrectal ultrasound (TRUS) (median difference, 23.33%), whereas on US images the target is overestimated compared with MR-based contouring (median difference, 13.25%). Although there are certain differences among the results given by various PID techniques, the differences are statistically insignificant for this small group of patients. Any dosimetric comparison between 2 PID techniques should also account for the limitations of each technique, to allow for an accurate quantification of data. Given that PID after permanent radioactive seed implant is mandatory for quality assurance, any imaging method–based PID (MR-CT, US-CT, and CT) available in a radiotherapy department can be indicative of the quality of the procedure.

  17. Dosimetric intercomparison of permanent Ho-166 seed's implants and HDR Ir-192 brachytherapy in breast cancer.

    PubMed

    de Campos, Tarcisio Passos Ribeiro; Nogueira, Luciana Batista; Trindade, Bruno; Cuperschmid, Ethel Mizrahy

    2016-01-01

    To provide a comparative dosimetric analysis of permanent implants of Ho(166)-seeds and temporary HDR Ir(192)-brachytherapy through computational simulation. Brachytherapy with Ir(192)-HDR or LDR based on temporary wires or permanent radioactive seed implants can be used as dose reinforcement for breast radiation therapy. Permanent breast implants have not been a practical clinical routine; although, I(125) and Pd(103)-seeds have already been reported. Biodegradable Ho(166)-ceramic-seeds have been addressed recently. Simulations of implants of nine Ho(166)-seeds and equivalent with HDR Ir(192)-brachytherapy were elaborated in MCNP5, shaped in a computational multivoxel simulator which reproduced a female thorax phantom. Spatial dose rate distributions and dose-volume histograms were generated. Protocol's analysis involving exposure time, seed's activities and dose were performed. Permanent Ho(166)-seed implants presented a maximum dose rate per unit of contained activity (MDR) of 1.1601 μGy h(-1) Bq(-1); and, a normalized MDR in standard points (8 mm, equidistant to 03-seeds - SP1, 10 mm - SP2) of 1.0% (SP1) and 0.5% (SP2), respectively. Ir(192)-brachytherapy presented MDR of 4.3945 × 10(-3) μGy h(-1) Bq(-1); and, 30% (SP1), and 20% (SP2). Therefore, seed's implant activities of 333 MBq (Ho(166)) and 259 GBq (Ir(192)) produced prescribed doses of 58 Gy (SP1; 5d) and 56 Gy (SP1, 5 fractions, 6 min), respectively. Breast Ho(166)-implants of 37-111 MBq are attractive due to the high dose rate near 6-10 mm from seeds, equivalent to Ir(192)-brachytherapy of 259 GBq (3 fractions, 6 min) providing similar dose in standard points at a week; however, with spatial dose distribution better confined. The seed positioning can be adjusted for controlling the breast tumor, in stages I and II, in flat and deep tumors, without any breast volumetric limitation.

  18. Permanent and removable implants for the brachytherapy of brain tumors

    SciTech Connect

    Gutin, P.H.; Phillips, T.L.; Hosobuchi, Y.

    1981-10-01

    Thirty-seven patients harboring primary or metastatic brain tumors were treated with 40 implantations of radioactive sources (/sup 192/Ir, /sup 198/Au, or /sup 125/I) using stereotactic neurosurgical techniques. Most tumors had recurred after surgery, whole brain irradiation, and treatment with all feasible chemotherapeutic agents. Sixteen of the 40 implants were pregnant; 24 were mounted in plastic catheters for removal after the desired dose had been delivered. One or more sources were placed in each tumor to deliver 3500-7350 rad to the tumor's periphery for /sup 198/Au, 4,000-12,000 rad for /sup 192/Ir, and 3,000-20,000 rad for /sup 125/I. Three of the six patients treated with /sup 192/Ir had objective responses for 2, 4, and 12 months, and two stabilized for 8 and 11 months. Seven of the 11 patients treated with /sup 198/Au were evaluable: three responded for 3, 5, and 37 + months, one deteriorating patient with a recurrent tumor stabilized for 6 months, and two deteriorated despite treatment. One patient received an interstitial ''boost'' dose with /sup 198/Au after whole brain irradiation and stabilized for 15 months before developing spinal metastases. Six patients received permanent implants with low activity /sup 125/I. Three of these patients had blioblastomas or anaplastic astrocytomas; all continued to deteriorate despite the interstitial irradiation, presumably because the dose rat was too low. One patient with a low-grade astrocytoma (optic chiasm) responded dramatically to permanent, low activity /sup 125/I implants (11 + months). Another (hypothalamic glioma) had a permanent /sup 125/I implant, responded, as was stable at 9 months when external irradiation was administered. One patient with a suprasellar ''teratoid'' tumor stabilized for 10 months.

  19. [Brachytherapy].

    PubMed

    Itami, Jun

    2014-12-01

    Brachytherapy do require a minimal expansion of CTV to obtain PTV and it is called as ultimate high precision radiation therapy. In high-dose rate brachytherapy, applicators will be placed around or into the tumor and CT or MRI will be performed with the applicators in situ. With such image-guided brachytherapy (IGBT) 3-dimensional treatment planning becomes possible and DVH of the tumor and organs at risk can be obtained. It is now even possible to make forward planning satisfying dose constraints. Traditional subjective evaluation of brachytherapy can be improved to the objective one by IGBT. Brachytherapy of the prostate cancer, cervical cancer, and breast cancer with IGBT technique was described.

  20. Long-Term Outcome for Clinically Localized Prostate Cancer Treated With Permanent Interstitial Brachytherapy

    SciTech Connect

    Taira, Al V.; Merrick, Gregory S.; Butler, Wayne M.; Galbreath, Robert W.; Lief, Jonathan; Adamovich, Edward; Wallner, Kent E.

    2011-04-01

    Purpose: To present the largest series of prostate cancer brachytherapy patients treated with modern brachytherapy techniques and postimplant day 0 dosimetric evaluation. Methods and Materials: Between April 1995 and July 2006, 1,656 consecutive patients were treated with permanent interstitial brachytherapy. Risk group stratification was carried out according to the Mt. Sinai guidelines. Median follow-up was 7.0 years. The median day 0 minimum dose covering at least 90% of the target volume was 118.8% of the prescription dose. Cause of death was determined for each deceased patient. Multiple clinical, treatment, and dosimetric parameters were evaluated for impact on the evaluated survival parameters. Results: At 12 years, biochemical progression-free survival (bPFS), cause-specific survival (CSS), and overall survival (OS) for the entire cohort was 95.6%, 98.2%, and 72.6%, respectively. For low-, intermediate-, and high-risk patients, bPFS was 98.6%, 96.5%, and 90.5%; CSS was 99.8%, 99.3%, and 95.2%; and OS was 77.5%, 71.1%, and 69.2%, respectively. For biochemically controlled patients, the median posttreatment prostate-specific antigen (PSA) concentration was 0.02 ng/ml. bPFS was most closely related to percent positive biopsy specimens and risk group, while Gleason score was the strongest predictor of CSS. OS was best predicted by patient age, hypertension, diabetes, and tobacco use. At 12 years, biochemical failure and cause-specific mortality were 1.8% and 0.2%, 5.1% and 2.1%, and 10.4% and 7.1% for Gleason scores 5 to 6 and 7 and {>=}8, respectively. Conclusions: Excellent long-term outcomes are achievable with high-quality brachytherapy for low-, intermediate-, and high-risk patients. These results compare favorably to alternative treatment modalities including radical prostatectomy.

  1. Safety and efficacy of concomitant chemotherapeutic wafers and iodine-125 seeds for recurrent glioblastoma.

    PubMed

    Ko, Andrew L; Fink, Kathleen R; Stelzer, Keith M; Silbergeld, Daniel L

    2012-01-01

    Patients with recurrent malignant gliomas have a uniformly poor prognosis. However, further treatment is often warranted at the time of recurrence. Low-activity implanted brachytherapeutic devices, such as iodine-125 seeds, and implantable chemotherapeutic devices such as 1, 3-bis (2-chloroethyl)-nitrosourea (BCNU) impregnated polymer wafers (Gliadel(®)) have been shown to be safe and modestly effective, but a comparison of combination therapy versus Gliadel(®) implantation alone has not been performed. We retrospectively examined 24 patients following re-resection of recurrent glioblastoma, with 17 patients undergoing implantation of both Gliadel(®) and iodine-125 seeds, and 7 patients undergoing implantation of Gliadel(®) only. Outcomes examined included adverse events, survival after re-resection (SAR), and time to tumor progression after re-resection (PAR). Implantation of both Gliadel(®) and low activity iodine-125 seeds is safe with only two wound infections noted, a complication rate comparable to previous reports. The combination appears to confer a median SAR benefit if the activity per tumor resection volume exceeds 0.8 mCi/mL (60 versus 31 weeks, P = 0.02), and this benefit remained significant on multivariate analysis (HR =0.26 [CI:0.07-0.93], P = 0.03). Gross total resection of tumor was also significantly associated with longer time to PAR (HR =5.4 [CI: 1.13-26.0], P = 0.03). The concomitant use of Gliadel(®) and low activity iodine-125 seeds following re-resection of recurrent glioblastoma is safe. Our study demonstrated a significant benefit in SAR if the iodine-125 activity per tumor volume is greater than 0.8 mCi/mL. While our sample size is small, our results are in agreement with previous studies demonstrating the efficacy of combination treatment.

  2. Brachytherapy

    MedlinePlus

    ... Who will be involved in this procedure? The delivery of brachytherapy requires a treatment team, including a ... are specially trained technologists who may assist in delivery of the treatments. The radiation therapy nurse provides ...

  3. Comparison between high and low source activity seeds for I-125 permanent seed prostate brachytherapy.

    PubMed

    Masucci, Giuseppina Laura; Donath, David; Tétreault-Laflamme, Audrey; Carrier, Jean-François; Hervieux, Yannick; Larouche, Renée Xavière; Bahary, Jean-Paul; Taussky, Daniel

    2010-11-01

    To compare low (mean 0.44, SD ± 0.0163 mCi) with high source activity (0.61 ± 0.0178 mCi) in I(125) permanent seed brachytherapy regarding seed loss, dosimetric outcome, and toxicity. The study included 199 patients with prostate cancer treated by permanent seed brachytherapy alone: the first 105 with seeds of lower activity (first cohort), the following 94 with higher seed activity (second cohort). The V100, V150, V200, and D90 were analyzed on the CT scan 30 days after implantation (CTD30). The V100, V150, and D2 of the rectum were also calculated on CTD30. Seed loss was determined 30 days after implantation. Urinary toxicity was measured with the International Prostate Symptom Score (IPSS) questionnaire. Lower seed activity was associated with lower V150 and V200 (p = 0.01 and p ≤ 0.001, respectively) on CTD30. More patients had a V100 <90% and D90 <140 Gy in the lower activity cohort (p = 0.098 for D90 and p = 0.029 for V100) on CTD30. There was no difference between cohorts in dose to the rectum (p = 0.325-0.516) or difference in patients' IPSS score from baseline (p = 0.0.117-0.618), although there was a trend toward more urinary toxicity at 4 and 8 months for high activity seeds. Seed loss as a percentage of implanted seeds was not different (p = 0.324). Higher seed activity (I(125) ≥ 0.6 mCi) results in at least equal V100 and D90 on CTD30. However, dose inhomogeneity and a trend toward more urinary toxicity at 4 and 8 months after treatment may lead to a higher long-term urinary complications. Copyright © 2010 Elsevier Inc. All rights reserved.

  4. Rectal-wall dose dependence on postplan timing after permanent-seed prostate brachytherapy

    SciTech Connect

    Taussky, Daniel; Yeung, Ivan; Williams, Theresa; Pearson, Shannon; McLean, Michael; Pond, Gregory; Crook, Juanita . E-mail: Juanita.crook@rmp.uhn.on.ca

    2006-06-01

    Purpose: Dose to rectal wall after permanent-seed prostate brachytherapy is dependent on distance between posterior prostatic seeds and anterior rectal wall and is influenced by postimplant periprostatic edema. We analyzed the effect of postplan timing on anterior rectal-wall dose. Methods and Materials: Twenty patients received permanent seed {sup 125}I brachytherapy as monotherapy (145 Gy). Implants were preplanned by use of transrectal ultrasound (TRUS) and carried out by use of preloaded needles. Postimplant dosimetry was calculated by use of magnetic resonance imaging-computed tomography fusion on Days 1, 8, and 30. The anterior rectal-wall dose is reported as the isodose enclosing 1.0 or 2.0 cc of rectal wall and as the RV100 in cc. Results: The dose to rectal wall increased progressively over time. The median increase in dose to 1.0 cc of rectal wall (RD [1 cc]) from Day 1 to 30 was 39.2 Gy (p < 0.001). RV100 increased from a median of 0.07 cc on Day 1 to 0.67 cc on Day 30. The most significant predictor of rectal-wall dose (RD [1 cc], RD [2 cc], or RV100) was the time of evaluation (p < 0.001). Conclusion: Although periprostatic edema cannot be quantified by postimplant imaging, the dose to the anterior rectal wall increases significantly over time as prostatic and periprostatic edema resolve. Critical-organ dose reporting and guidelines for minimizing toxicity must take into account the time of the assessment.

  5. Iodine-125 radiolabeling of silver nanoparticles for in vivo SPECT imaging

    PubMed Central

    Chrastina, Adrian; Schnitzer, Jan E

    2010-01-01

    Silver nanoparticles are increasingly finding applications in medicine; however, little is known about their in vivo tissue distribution. Here, we have developed a rapid method for radiolabeling of silver nanoparticles with iodine-125 in order to track in vivo tissue uptake of silver nanoparticles after systemic administration by biodistribution analysis and single-photon emission computerized tomography (SPECT) imaging. Poly(N-vinyl-2 -pyrrolidone)-capped silver nanoparticles with an average size of 12 nm were labeled by chemisorption of iodine-125 with a > 80% yield of radiolabeling efficiency. Radiolabeled silver nanoparticles were intravenously injected in Balb/c mice, and the in vivo distribution pattern of these nanoparticles was evaluated by noninvasive whole-body SPECT imaging, which revealed uptake of the nanoparticles in the liver and spleen. Biodistribution analysis confirmed predominant accumulation of the silver nanoparticles in the spleen (41.5%ID/g) and liver (24.5%ID/g) at 24 h. Extensive uptake in the tissues of the reticuloendothelial system suggests that further investigation of silver nanoparticle interaction with hepatic and splenic tissues at the cellular level is critical for evaluation of the in vivo effects and potential toxicity of silver nanoparticles. This method enables rapid iodine-125 radiolabeling of silver nanoparticles with a specific activity sufficient for in vivo imaging and biodistribution analysis. PMID:20856841

  6. TPS-guided interstitial Iodine-125 implantation in patients with oral cavity and maxillofacial carcinomas.

    PubMed

    Meng, J; Zhang, J; Zhuang, Q-W; Wang, X; Li, Z-P; Gu, Q-P

    2014-10-01

    To investigate the efficacy as well as the complications involved in the use of interstitial Iodine-125 implantation for the treatment of oral cavity and maxillofacial carcinomas. Fifteen patients with oral cavity and maxillofacial carcinomas received treatment planning system (TPS)-guided interstitial Iodine-125 implantation. The apparent activity per particle ranged from 0.6 mCi (2.22MBq) to 0.7 mCi (2.59MBq). The matched peripheral dose delivered by radioactive seeds ranged from 90 to 120 Gy. The efficacy of the treatment and the postoperative complications were evaluated during follow-up. The seeds were implanted successfully in all 15 patients and median number of seeds implanted was 36.53. CT scans were performed in all patients at 1-6 months postoperatively. During follow-up at 6-27 months, seed migration occurred and a good local tumor control was achieved with an overall response of 86.7%. No severe side effects were observed. TPS-guided interstitial Iodine-125 implantation is an effective and safe procedure with minimal invasiveness for the treatment of oral cavity and maxillofacial carcinomas, and it effectively prevents the recurrence of cancer and short-term lymphatic metastasis.

  7. Analysis of the Contribution of Charge Transport in Iodine-125 induced DNA Damage

    PubMed Central

    Ndlebe, Thabisile; Panyutin, Igor; Neumann, Ronald

    2009-01-01

    Auger electron emitters, like iodine-125, are the radionuclides of choice for gene-targeted radiotherapy. The highly localized damage they induced in DNA is produced by three mechanisms: direct damage by the emitted Auger electrons, indirect damage by diffusible free radicals produced by Auger electrons travelling in water, and charge neutralization of the residual, highly positively charged, tellurium daughter atom by stripping electrons from covalent bonds of neighboring residues. The purpose of our work was to determine whether these mechanisms proceed through an intermediate energy transfer step along DNA. It was proposed that this intermediate step proceeds through the charge transport mechanism in DNA. Conventional charge transport has been described as either a hopping mechanism initiated by charge injection into DNA and propagated by charge migration along the DNA, or a tunneling mechanism in which charge moves directly from a donor to an acceptor within DNA. Well-known barriers for the hopping mechanism were used to probe the role of charge transport in 125I induced DNA damage. We studied their effect on the distribution of DNA breaks produced by the decay of iodine-125 in samples frozen at −80°C. We found that these barriers had no measurable effect on the iodine-125 breaks distribution. PMID:20041764

  8. Dose escalation in permanent brachytherapy for prostate cancer: dosimetric and biological considerations

    NASA Astrophysics Data System (ADS)

    Li, X. Allen; Wang, Jian Z.; Stewart, Robert D.; Di Biase, Steven J.

    2003-09-01

    No prospective dose escalation study for prostate brachytherapy (PB) with permanent implants has been reported. In this work, we have performed a dosimetric and biological analysis to explore the implications of dose escalation in PB using 125I and 103Pd implants. The concept of equivalent uniform dose (EUD), proposed originally for external-beam radiotherapy (EBRT), is applied to low dose rate brachytherapy. For a given 125I or 103Pd PB, the EUD for tumour that corresponds to a dose distribution delivered by EBRT is calculated based on the linear quadratic model. The EUD calculation is based on the dose volume histogram (DVH) obtained retrospectively from representative actual patient data. Tumour control probabilities (TCPs) are also determined in order to compare the relative effectiveness of different dose levels. The EUD for normal tissue is computed using the Lyman model. A commercial inverse treatment planning algorithm is used to investigate the feasibility of escalating the dose to prostate with acceptable dose increases in the rectum and urethra. The dosimetric calculation is performed for five representative patients with different prostate sizes. A series of PB dose levels are considered for each patient using 125I and 103Pd seeds. It is found that the PB prescribed doses (minimum peripheral dose) that give an equivalent EBRT dose of 64.8, 70.2, 75.6 and 81 Gy with a fraction size of 1.8 Gy are 129, 139, 150 and 161 Gy for 125I and 103, 112, 122 and 132 Gy for 103Pd implants, respectively. Estimates of the EUD and TCP for a series of possible prescribed dose levels (e.g., 145, 160, 170 and 180 Gy for 125I and 125, 135, 145 and 155 for 103Pd implants) are tabulated. The EUD calculation was found to depend strongly on DVHs and radiobiological parameters. The dosimetric calculations suggest that the dose to prostate can be escalated without a substantial increase in both rectal and urethral dose. For example, increasing the PB prescribed dose from 145 to

  9. Outpatient template-guided permanent interstitial brachytherapy using (131)Cs in gynecologic malignancies: Initial report.

    PubMed

    Feddock, Jonathan; Aryal, Prakash; Steber, Cole; Edwards, Jason; Cheek, Dennis; Randall, Marcus

    Optimal curative intent brachytherapy for certain gynecologic cancers requires interstitial brachytherapy, often using template-guided techniques such as a Syed-Neblett implant. Whether high or low dose rate (LDR), these procedures pose significant risks to patients, partly attributable to the prolonged period of bed rest. Published results of free-handed permanent interstitial brachytherapy (PIB) with (131)Cs demonstrate it to be an effective modality for the management of small volume gynecologic cancers. This report is the first to describe a permanent template-guided interstitial technique using (131)Cs for gynecologic cancers, performed as an LDR outpatient procedure. Five sequential patients with recurrent or primary gynecologic malignancies underwent template-guided PIB using (131)Cs. A posttreatment planning CT was obtained immediately after the procedure and again 3-4 weeks later. Both CT data sets were fused and the relative positions compared to assess for migration in the x, y, and z planes. Seed positions as well as dosimetric parameters including D90, D100, V100, and the dose to 2 cc of rectum and bladder were compared to quantify migration of sources and the resulting effect, if any, on the treatment. The median age was 69 years (range 64-85). All patients received a template-guided (131)Cs PIB implant to treat gross disease. All 5 patients had significant medical comorbidities that limited treatment options. Considering all 5 patients, a total of 40 interstitial needles were placed. Ten needles carried only Vicryl-stranded sources, and 30 needles carried a combination of stranded (131)Cs seeds and free seeds. Needle count was between 6 and 10 needles per patient, with active lengths of 4-10 cm. The median dose was 30 Gy (range 25-55 Gy) to permanent decay, enabling a cumulative median biological effective dose 91.5 Gy (range 60.9-92.1 Gy) and equivalent dose at 2 Gy per fraction 75.9 Gy (range 50.7-76.8 Gy). All implants were performed as

  10. Evaluation of source displacement and dose--volume changes after permanent prostate brachytherapy with stranded seeds.

    PubMed

    Pinkawa, Michael; Asadpour, Branka; Gagel, Bernd; Piroth, Marc D; Borchers, Holger; Jakse, Gerhard; Eble, Michael J

    2007-08-01

    The aim of the study was to analyze source displacements and dose-volume changes in the first month after a permanent implant. In 51 consecutive patients, CT scans were performed at the postoperative day (day 1) and one month (day 30) after an (125)I implant with stranded seeds. Seed positions were determined relative to pelvic bones for five seeds at the base and five seeds at the apex for each patient (n=510) and compared. To verify these results, treatment margins (TM=distance of prescription isodose to prostate) and displacements of the prostate surface (anterior/posterior/right/left/superior/inferior) relative to pelvic bones were measured. Seed positions have moved significantly between day 1 and 30 in the posterior (mean 1.0mm; p<0.001) and inferior (mean 3.8mm; p<0.001) directions. TM increased particularly at the posterior (mean 2.2mm; p<0.001) and apical (median 3.0mm; p<0.001) prostate contour with decreasing oedema. With a stable apex position and a mean inward posterior surface displacement of 1.1mm (p<0.001) relative to pelvic bones, seed displacements could be well correlated with prescription isodose displacements (Pearson correlation coefficients >or=0.81; p<0.001). Both changes of prostate volume and seed displacements need to be considered to explain dosimetric changes after permanent prostate brachytherapy.

  11. American Society for Radiation Oncology (ASTRO) and American College of Radiology (ACR) practice guideline for the transperineal permanent brachytherapy of prostate cancer.

    PubMed

    Rosenthal, Seth A; Bittner, Nathan H J; Beyer, David C; Demanes, D Jeffrey; Goldsmith, Brian J; Horwitz, Eric M; Ibbott, Geoffrey S; Lee, W Robert; Nag, Subir; Suh, W Warren; Potters, Louis

    2011-02-01

    Transperineal permanent prostate brachytherapy is a safe and efficacious treatment option for patients with organ-confined prostate cancer. Careful adherence to established brachytherapy standards has been shown to improve the likelihood of procedural success and reduce the incidence of treatment-related morbidity. A collaborative effort of the American College of Radiology (ACR) and American Society for Therapeutic Radiation Oncology (ASTRO) has produced a practice guideline for permanent prostate brachytherapy. The guideline defines the qualifications and responsibilities of all the involved personnel, including the radiation oncologist, physicist and dosimetrist. Factors with respect to patient selection and appropriate use of supplemental treatment modalities such as external beam radiation and androgen suppression therapy are discussed. Logistics with respect to the brachytherapy implant procedure, the importance of dosimetric parameters, and attention to radiation safety procedures and documentation are presented. Adherence to these practice guidelines can be part of ensuring quality and safety in a successful prostate brachytherapy program.

  12. Swelling of the prostate gland by permanent brachytherapy may affect seed migration.

    PubMed

    Kono, Yuzuru; Kubota, Kazuo; Aruga, Takashi; Ishibashi, Akihiko; Morooka, Miyako; Ito, Kimiteru; Itami, Jun; Kanemura, Mikio; Minowada, Shigeru; Tanaka, Takashi

    2010-12-01

    The purpose was to monitor implanted seeds and to determine factors contributing to seed migration after permanent prostate brachytherapy. Sixty-two consecutive patients with Stage 1 prostate cancer who underwent brachytherapy with (125)I seeds between February 2008 and May 2009 were studied prospectively. On post-operative days 1, 7 and 30, scintigraphy was added to conventional radiography to monitor the migration of the implanted seeds. The prostate volume was measured during the pre-planning stage using ultrasound and during the post-planning stage using computed tomography on post-operative days 0 and 30. Magnetic resonance imaging was performed on day 30. Of the 4843 seeds implanted in the prostates of 62 patients, 108 seeds (2.2%) in 43 patients (69.4%) exhibited seed migration. Thirty-five seeds could not be identified using any of the imaging modalities and were likely passed during urination (0.7% of the total number of seeds). The maximum number of migrated seeds in one patient was 10 of the 85 implanted seeds. The fraction of patients with seed migration or loss increased from 27.4% on day 1 to 69.4% on day 30. The number of seeds that had migrated from the prostate increased from 48 (0.1% of the total number of seeds) on 1 day to 78 (1.0%) on day 7 and 108 (2.2%) on day 30. Of the seeds lost from the prostate, 38.9% embolized to the lungs. The seed loss during the first post-operative month was closely correlated with the swelling of the prostate gland between the pre-planning measurement and the post-planning measurement performed on day 0 (P < 0.0001). Prostate swelling between the pre-planning and post-planning (day 0) measurements was significantly associated with seed migration, and adequate attention should be given to this issue.

  13. Impact of short course hormonal therapy on overall and cancer specific survival after permanent prostate brachytherapy

    SciTech Connect

    Beyer, David C. . E-mail: dbeyer@azoncology.com; McKeough, Timothy; Thomas, Theresa

    2005-04-01

    Purpose: To review the impact of prior hormonal therapy on 10-year overall and prostate cancer specific survival after primary brachytherapy. Methods and Materials: A retrospective review was performed on the Arizona Oncology Services tumor registry for 2,378 consecutive permanent prostate brachytherapy cases from 1988 through 2001. Hormonal therapy was administered before the implant in 464 patients for downsizing of the prostate or at the discretion of the referring physician. All deceased patients with known clinical recurrence were considered to have died of prostate cancer, irrespective of the immediate cause of death. Risk groups were defined, with 1,135 favorable (prostate-specific antigen [PSA] < 10, Gleason < 7, Stage T1-T2a), 787 intermediate (single adverse feature), and 456 unfavorable (two or more adverse features) patients. Kaplan-Meier actuarial survival curves were generated for both overall and cause-specific survival from the time of treatment. Multivariate analysis was performed to assess the impact of hormonal intervention in comparison with known risk factors of grade, PSA, and age. Results: With follow-up ranging up to 12.6 years and a median of 4.1 year, a total of 474 patients died, with 67 recorded as due to prostate cancer. Overall and cause-specific 10-year survival rates are 43% and 88%, respectively. Overall survival is 44% for the hormone naive patients, compared with 20% for the hormone-treated cohort (p = 0.02). The cancer-specific survival is 89% vs. 81% for the same groups (p = 0.133). Multivariate analysis confirms the significance of age > 70 years (p = 0.0013), Gleason score {>=} 7 (p = 0.0005), and prior hormone use (p = 0.0065) on overall survival. Conclusions: At 10 years, in prostate cancer patients receiving brachytherapy, overall survival is worse in men receiving neoadjuvant hormonal therapy, compared with hormone naive patients. This does not appear to be due to other known risk factors for survival (i.e., stage, grade

  14. Inverse planning optimization for hybrid prostate permanent-seed implant brachytherapy plans using two source strengths.

    PubMed

    Cunha, J Adam M; Pickett, Barby; Pouliot, Jean

    2010-06-03

    The purpose is to demonstrate the ability to generate clinically acceptable prostate permanent seed implant plans using two seed types which are identical except for their activity. The IPSA inverse planning algorithms were modified to include multiple dose matrices for the calculation of dose from different sources, and a selection algorithm was implemented to allow for the swapping of source type at any given source position. Five previously treated patients with a range of prostate volumes from 20-48 cm3 were re-optimized under two hybrid scenarios: (1) using 0.32 and 0.51 mGy m2 / h 125I, and (2) using 0.64 and 0.76 mGy m2 / h 125I. Isodose lines were generated and dosimetric indices , V150Prostate, D90Prostate, V150Urethra, V125Urethra, V120Urethra,V100Urethra, and D10Urethra were calculated. The algorithm allows for the generation of single-isotope, multi-activity hybrid brachytherapy plans. By dealing with only one radionuclide, but of different activity, the biology is unchanged from a standard plan. All V100Prostate were within 2.3 percentage points for every plan and always above the clinically desirable 95%. All V150Urethra were identically zero, and V120Urethra is always below the clinically acceptable value of 1.0 cm3. Clinical optimization times for the hybrid plans are still under one minute, for most cases. It is possible to generate clinically advantageous brachytherapy plans (i.e. obtain the same quality dose distribution as a standard single-activity plan) while incorporating leftover seeds from a previous patient treatment. This method will allow a clinic to continue to provide excellent patient care, but at a reduced cost. Multi-activity hybrid plans were equal in quality (as measured by the standard dosimetric indices) to plans with seeds of a single activity. Despite the expanded search space, optimization times for these studies were still under two minutes on a modern day laptop and can be reduced to below one minute in a clinical setting

  15. Definition of medical event is to be based on the total source strength for evaluation of permanent prostate brachytherapy: A report from the American Society for Radiation Oncology.

    PubMed

    Nag, Subir; Demanes, D Jeffrey; Hagan, Michael; Rivard, Mark J; Thomadsen, Bruce R; Welsh, James S; Williamson, Jeffrey F

    2011-10-01

    The Nuclear Regulatory Commission deems it to be a medical event (ME) if the total dose delivered differs from the prescribed dose by 20% or more. A dose-based definition of ME is not appropriate for permanent prostate brachytherapy as it generates too many spurious MEs and thereby creates unnecessary apprehension in patients, and ties up regulatory bodies and the licensees in unnecessary and burdensome investigations. A more suitable definition of ME is required for permanent prostate brachytherapy. The American Society for Radiation Oncology (ASTRO) formed a working group of experienced clinicians to review the literature, assess the validity of current regulations, and make specific recommendations about the definition of an ME in permanent prostate brachytherapy. The working group found that the current definition of ME in §35.3045 as "the total dose delivered differs from the prescribed dose by 20 percent or more" was not suitable for permanent prostate brachytherapy since the prostate volume (and hence the resultant calculated prostate dose) is dependent on the timing of the imaging, the imaging modality used, the observer variability in prostate contouring, the planning margins used, inadequacies of brachytherapy treatment planning systems to calculate tissue doses, and seed migration within and outside the prostate. If a dose-based definition for permanent implants is applied strictly, many properly executed implants would be improperly classified as an ME leading to a detrimental effect on brachytherapy. The working group found that a source strength-based criterion, of >20% of source strength prescribed in the post-procedure written directive being implanted outside the planning target volume is more appropriate for defining ME in permanent prostate brachytherapy. ASTRO recommends that the definition of ME for permanent prostate brachytherapy should not be dose based but should be based upon the source strength (air-kerma strength) administered.

  16. Customized dose prescription for permanent prostate brachytherapy: insights from a multicenter analysis of dosimetry outcomes.

    PubMed

    Stone, Nelson N; Potters, Louis; Davis, Brian J; Ciezki, Jay P; Zelefsky, Michael J; Roach, Mack; Fearn, Paul A; Kattan, Michael W; Stock, Richard G

    2007-12-01

    To investigate the biochemical control rate in patients undergoing permanent prostate brachytherapy as a function of the biologically effective dose (BED) and risk group. Six centers provided data on 3,928 permanent brachytherapy patients with postimplant dosimetry results. The mean prostate-specific antigen level was 8.9 ng/mL. (125)I was used in 2,293 (58%), (103)Pd in 1,635, and supplemental external beam radiotherapy in 882 (22.5%) patients. The patients were stratified into low- (n = 2,188), intermediate- (n = 1,188), and high- (n = 552) risk groups and into three BED groups of < 140 Gy (n = 524), 140-200 Gy (n = 2284), and >200 Gy (n = 1,115). Freedom from biochemical disease progression (biochemical freedom from failure [bFFF]) was determined using the American Society for Therapeutic Radiology Oncology and Phoenix definitions and calculated using the Kaplan-Meier method, with factors compared using the log-rank test. The 10-year prostate-specific antigen bFFF rate for the American Society for Therapeutic Radiology Oncology and Phoenix definitions was 79.2% and 70%, respectively. The corresponding bFFF rates for the low-, intermediate-, and high-risk groups was 84.1% and 78.1%, 76.8% and 63.6%, and 64.4% and 58.2%, respectively (p < 0.0001). The corresponding bFFF rate for the three BED groups was 56.1% and 41.4%, 80% and 77.9%, and 91.1% and 82.9% (p < 0.0001). The corresponding bFFF rate for the low-risk patients by dose group was 69.8% and 49.8%, 86% and 85.2%, and 88.1% and 88.3% for the low-, intermediate, and high-dose group, respectively (p <0.0001). The corresponding bFFF rate for the intermediate-risk patients by dose group was 52.9% and 23.1%, 74.1% and 77.7%, and 94.3% and 88.8% for the low-, intermediate-, and high-dose group, respectively (p < 0.0001). The corresponding bFFF rate for high-risk patients by dose group was 19.2% and 41.7%, 61.8% and 53.2%, and 90% and 69.6% for the low-, intermediate-, and high-dose group, respectively (p < 0

  17. Customized Dose Prescription for Permanent Prostate Brachytherapy: Insights From a Multicenter Analysis of Dosimetry Outcomes

    SciTech Connect

    Stone, Nelson N. Potters, Louis; Davis, Brian J.; Ciezki, Jay P.; Zelefsky, Michael J.; Roach, Mack; Fearn, Paul A. B.A.; Kattan, Michael W.; Stock, Richard G.

    2007-12-01

    Purpose: To investigate the biochemical control rate in patients undergoing permanent prostate brachytherapy as a function of the biologically effective dose (BED) and risk group. Methods and Materials: Six centers provided data on 3,928 permanent brachytherapy patients with postimplant dosimetry results. The mean prostate-specific antigen level was 8.9 ng/mL. {sup 125}I was used in 2,293 (58%), {sup 103}Pd in 1,635, and supplemental external beam radiotherapy in 882 (22.5%) patients. The patients were stratified into low- (n = 2,188), intermediate- (n = 1,188), and high- (n = 552) risk groups and into three BED groups of < 140 Gy (n = 524), 140-200 Gy (n = 2284), and >200 Gy (n = 1,115). Freedom from biochemical disease progression (biochemical freedom from failure [bFFF]) was determined using the American Society for Therapeutic Radiology Oncology and Phoenix definitions and calculated using the Kaplan-Meier method, with factors compared using the log-rank test. Results: The 10-year prostate-specific antigen bFFF rate for the American Society for Therapeutic Radiology Oncology and Phoenix definitions was 79.2% and 70%, respectively. The corresponding bFFF rates for the low-, intermediate-, and high-risk groups was 84.1% and 78.1%, 76.8% and 63.6%, and 64.4% and 58.2%, respectively (p < 0.0001). The corresponding bFFF rate for the three BED groups was 56.1% and 41.4%, 80% and 77.9%, and 91.1% and 82.9% (p < 0.0001). The corresponding bFFF rate for the low-risk patients by dose group was 69.8% and 49.8%, 86% and 85.2%, and 88.1% and 88.3% for the low-, intermediate, and high-dose group, respectively (p <0.0001). The corresponding bFFF rate for the intermediate-risk patients by dose group was 52.9% and 23.1%, 74.1% and 77.7%, and 94.3% and 88.8% for the low-, intermediate-, and high-dose group, respectively (p < 0.0001). The corresponding bFFF rate for high-risk patients by dose group was 19.2% and 41.7%, 61.8% and 53.2%, and 90% and 69.6% for the low-, intermediate

  18. Sequential evaluation of prostate edema after permanent seed prostate brachytherapy using CT-MRI fusion

    SciTech Connect

    Taussky, Daniel; Austen, Lyn; Toi, Ants; Yeung, Ivan; Williams, Theresa; Pearson, Shannon; McLean, Michael; Pond, Gregory; Crook, Juanita . E-mail: juanita.crook@rmp.uhn.on.ca

    2005-07-15

    Purpose: To analyze the extent and time course of prostate edema and its effect on dosimetry after permanent seed prostate brachytherapy. Methods and Materials: Twenty patients scheduled for permanent seed {sup 125}I prostate brachytherapy agreed to a prospective study on postimplant edema. Implants were preplanned using transrectal ultrasonography. Postimplant dosimetry was calculated using computed tomography-magnetic resonance imaging (CT-MRI) fusion on the day of the implant (Day 1) and Days 8 and 30. The prostate was contoured on MRI, and the seeds were located on CT. Factors investigated for an influence on edema were the number of seeds and needles, preimplant prostate volume, transitional zone index (transition zone volume divided by prostate volume), age, and prostate-specific antigen level. Prostate dosimetry was evaluated by the percentage of the prostate volume receiving 100% of the prescribed dose (V{sub 100}) and percentage of prescribed dose received by 90% of the prostate volume (D{sub 90}). Results: Prostate edema was maximal on Day 1, with the median prostate volume 31% greater than preimplant transrectal ultrasound volume (range, 0.93-1.72; p < 0.001) and decreased with time. It was 21% greater than baseline at Day 8 (p = 0.013) and 5% greater on Day 30 (p < 0.001). Three patients still had a prostate volume greater than baseline by Day 30. The extent of edema depended on the transition zone volume (p = 0.016) and the preplan prostate volume (p 0.003). The median V{sub 100} on Day 1 was 93.6% (range, 86.0-98.2%) and was 96.3% (range, 85.7-99.5%) on Day 30 (p = 0.079). Patients with a Day 1 V{sub 100} >93% were less affected by edema resolution, showing a median increase in V{sub 100} of 0.67% on Day 30 compared with 2.77% for patients with a V{sub 100} <93 % on Day 1. Conclusion: Despite the extreme range of postimplant edema, the effect on dosimetry was less than expected. Dose coverage of the prostate was good for all patients during Days 1

  19. A new inexpensive customized plaque for choroidal melanoma iodine-125 plaque therapy

    SciTech Connect

    Vine, A.K.; Tenhaken, R.K.; Diaz, R.F.; Maxson, B.B.; Lichter, A.S.

    1989-04-01

    The authors have developed a new inexpensive precious metal alloy plaque for use in customized iodine-125 plaque therapy. Each plaque is formed from two flat circular gold/palladium foils which are used in dental crown work. Using a simple manual mechanism, the two forms are stamped over a customized acrylic die shaped to the dimensions of the tumor base plus a 2-mm margin. Completed plaques consist of a back wall, a 2-mm side wall, and a 1.5-mm wide lip with holes for suture placement. Advantages include: simple construction from inexpensive components, customized shape, and iodine seeds that are readily visible on plane radiographs.

  20. [Intraoperative and post-implant dosimetry in patients treated with permanent prostate implant brachytherapy].

    PubMed

    Herein, András; Ágoston, Péter; Szabó, Zoltán; Jorgo, Kliton; Markgruber, Balázs; Pesznyák, Csilla; Polgár, Csaba; Major, Tibor

    2015-06-01

    The purpose of our work was to compare intraoperative and four-week post-implant dosimetry for loose and stranded seed implants for permanent prostate implant brachytherapy. In our institute low-dose-rate (LDR) prostate brachytherapy is performed with encapsulated I-125 isotopes (seeds) using transrectal ultrasound guidance and metal needles. The SPOT PRO 3.1 (Elekta, Sweden) system is used for treatment planning. In this study the first 79 patients were treated with loose seed (LS) technique, the consecutive patients were treated with stranded seed (SS) technique. During intraoperative planning the dose constraints were the same for both techniques. All LSs were placed inside the prostate capsule, while with SS a 2 mm margin around the prostate was allowed for seed positioning. The prescribed dose for the prostate was 145 Gy. This study investigated prostate dose coverage in 30-30 randomly selected patients with LS and SS. Four weeks after the implantation native CT and MRI were done and CT/MRI image fusion was performed. The target was contoured on MRI and the plan was prepared on CT data. To assess the treatment plan dose-volume histograms were used. For the target coverage V100, V90, D90, D100, for the dose inhomogeneity V150, V200, and the dose-homogeneity index (DHI), for dose conformality the conformal index (COIN) were calculated. Intraoperative and postimplant plans were compared. The mean V100 values decreased at four-week plan for SS (97% vs. 84%) and for LS (96% vs. 80%) technique, as well. Decrease was observed for all parameters except for the DHI value. The DHI increased for SS (0.38 vs. 0.41) and for LS (0.38 vs. 0.47) technique, as well. The COIN decreased for both techniques at four-week plan (SS: 0.63 vs. 0.57; LS: 0.67 vs. 0.50). All differences were significant except for the DHI value at SS technique. The percentage changes were not significant, except the COIN value. The dose coverage of the target decreased significantly at four-week plans

  1. Radioimmunoguided surgery using iodine 125 B72. 3 in patients with colorectal cancer

    SciTech Connect

    Cohen, A.M.; Martin, E.W. Jr.; Lavery, I.; Daly, J.; Sardi, A.; Aitken, D.; Bland, K.; Mojzisik, C.; Hinkle, G. )

    1991-03-01

    Preliminary data using B72.3 murine monoclonal antibody labeled with iodine 125 suggested that both clinically apparent as well as occult sites of colorectal cancer could be identified intraoperatively using a hand-held gamma detecting probe. We report the preliminary data of a multicenter trial of this approach in patients with primary or recurrent colorectal cancer. One hundred four patients with primary, suspected, or known recurrent colorectal cancer received an intravenous infusion of 1 mg of B72.3 monoclonal antibody radiolabeled with 7.4 x 10 Bq of iodine 125. Twenty-six patients with primary colorectal cancer and 72 patients with recurrent colorectal cancer were examined. Using the gamma detecting probe, 78% of the patients had localization of the antibody in their tumor; this included 75% of primary tumor sites and 63% of all recurrent tumor sites; 9.2% of all tumor sites identified represented occult sites detected only with the gamma detecting probe. The overall sensitivity was 77% and a predictive value of a positive detection was 78%. A total of 30 occult sites in 26 patients were identified. In patients with recurrent cancer, the antibody study provided unique data that precluded resection in 10 patients, and in another eight patients it extended the potentially curative procedure.

  2. Optimal equations for describing the relationship between prostate volume, number of sources, and total activity in permanent prostate brachytherapy.

    PubMed

    Aronowitz, Jesse N; Michalski, Jeff M; Merrick, Gregory S; Sylvester, John E; Crook, Juanita M; Butler, Wayne M; Mawson, Christie; Pratt, David; Naidoo, Devi; Karolczuk, Kathryn

    2010-04-01

    To determine whether there is an optimal type of mathematical equation for predicting seed and activity requirements for permanent prostate brachytherapy. Four institutions with extensive brachytherapy experience each submitted details of more than 40 implants. The data was used to generate power and linear equations to reflect the relationship between preimplant volume and the number of seeds implanted, and preimplant volume and the total implant activity. We compared the R and standard error of the generated equations to determine which type of equation better fit the data. For the limited range of prostate volumes commonly implanted (20-60 mL), power and linear equations predict seed and activity requirements comparably well. Linear and power equations are equally suitable for generating institution-specific nomograms.

  3. Dosimetric study of Cs-131, I-125, and Pd-103 seeds for permanent prostate brachytherapy.

    PubMed

    Yang, Ruijie; Wang, Junjie; Zhang, Hongzhi

    2009-12-01

    As a well-established single-modality approach for early-stage prostate cancer, transperineal interstitial permanent prostate brachytherapy (TIPPB) has gained increasing popularity due to its favorable clinical results. Currently, three isotopes, namely Cs-131, I-125, and Pd-103, are commercially available for TIPPB. This is the first study to systematically explore the dosimetric difference of these three isotopes for TIPPB. In total, 25 patients with T1-T2c prostate cancer previously implanted with I-125 seeds were randomly selected and replanned with Cs-131, I-125, and Pd-103 seeds to the prescription doses of 115, 145, and 125 Gy, respectively. The planning goals attempted were prostate V(p)100 approximately 95%, D(p)90 >or= 100%, and prostatic urethra D(u)10

  4. Iodine-125 cholesteryl iopanoate for measuring extent of atherosclerosis in rabbits.

    PubMed

    DeGalan, M R; Schwendner, S W; Skinner, R W; Longino, M A; Gross, M; Counsell, R E

    1988-04-01

    Rabbits rendered atherosclerotic by mechanical aortic de-endothelialization and 6 wk of cholesterol feeding were administered estradiol-17 beta-cypionate, an anti-atherogenic agent in rabbits. These animals were compared to a similar, untreated group and control animals fed a regular non-atherogenic diet. Iodine-125 cholesteryl iopanoate ([125I]Cl), a nonhydrolyzable cholesteryl ester derivative, was administered intravenously at regular intervals throughout the study. Six days after the last dose of [125I]Cl, the animals were scanned with a gamma camera. After animals were killed, tissue distribution of the 125I radioactivity showed a significant decrease of [125I]CI accumulation in the aorta of estrogen-treated as compared to untreated, cholesterol-fed animals. However, the accumulation of [125I]CI in the aortas was insufficient to accurately define the presence of atheroma by gamma camera scintigraphy.

  5. SU-F-19A-08: Optimal Time Release Schedule of In-Situ Drug Release During Permanent Prostate Brachytherapy

    SciTech Connect

    Cormack, R; Ngwa, W; Makrigiorgos, G; Tangutoori, S; Rajiv, K; Sridhar, S

    2014-06-15

    Purpose: Permanent prostate brachytherapy spacers can be used to deliver sustained doses of radiosentitizing drug directly to the target, in order to enhance the radiation effect. Implantable nanoplatforms for chemo-radiation therapy (INCeRTs) have a maximum drug capacity and can be engineered to control the drug release schedule. The optimal schedule for sensitization during continuous low dose rate irradiation is unknown. This work studies the optimal release schedule of drug for both traditional sensitizers, and those that work by suppressing DNA repair processes. Methods: Six brachytherapy treatment plans were used to model the anatomy, implant geometry and calculate the spatial distribution of radiation dose and drug concentrations for a range of drug diffusion parameters. Three state partial differential equations (cells healthy, damaged or dead) modeled the effect of continuous radiation (radiosensitivities α,β) and cellular repair (time tr) on a cell population. Radiosensitization was modeled as concentration dependent change in α,β or tr which with variable duration under the constraint of fixed total drug release. Average cell kill was used to measure effectiveness. Sensitization by means of both enhanced damage and reduced repair were studied. Results: Optimal release duration is dependent on the concentration of radiosensitizer compared to the saturation concentration (csat) above which additional sensitization does not occur. Long duration drug release when enhancing α or β maximizes cell death when drug concentrations are generally over csat. Short term release is optimal for concentrations below saturation. Sensitization by suppressing repair has a similar though less distinct trend that is more affected by the radiation dose distribution. Conclusion: Models of sustained local radiosensitization show potential to increase the effectiveness of radiation in permanent prostate brachytherapy. INCeRTs with high drug capacity produce the greatest

  6. SU-E-T-123: Anomalous Altitude Effect in Permanent Implant Brachytherapy Seeds

    SciTech Connect

    Watt, E; Spencer, DP; Meyer, T

    2015-06-15

    Purpose: Permanent seed implant brachytherapy procedures require the measurement of the air kerma strength of seeds prior to implant. This is typically accomplished using a well-type ionization chamber. Previous measurements (Griffin et al., 2005; Bohm et al., 2005) of several low-energy seeds using the air-communicating HDR 1000 Plus chamber have demonstrated that the standard temperature-pressure correction factor, P{sub TP}, may overcompensate for air density changes induced by altitude variations by up to 18%. The purpose of this work is to present empirical correction factors for two clinically-used seeds (IsoAid ADVANTAGE™ {sup 103}Pd and Nucletron selectSeed {sup 125}I) for which empirical altitude correction factors do not yet exist in the literature when measured with the HDR 1000 Plus chamber. Methods: An in-house constructed pressure vessel containing the HDR 1000 Plus well chamber and a digital barometer/thermometer was pumped or evacuated, as appropriate, to a variety of pressures from 725 to 1075 mbar. Current measurements, corrected with P{sub TP}, were acquired for each seed at these pressures and normalized to the reading at ‘standard’ pressure (1013.25 mbar). Results: Measurements in this study have shown that utilization of P{sub TP} can overcompensate in the corrected current reading by up to 20% and 17% for the IsoAid Pd-103 and the Nucletron I-125 seed respectively. Compared to literature correction factors for other seed models, the correction factors in this study diverge by up to 2.6% and 3.0% for iodine (with silver) and palladium respectively, indicating the need for seed-specific factors. Conclusion: The use of seed specific altitude correction factors can reduce uncertainty in the determination of air kerma strength. The empirical correction factors determined in this work can be applied in clinical quality assurance measurements of air kerma strength for two previously unpublished seed designs (IsoAid ADVANTAGE™ {sup 103}Pd and

  7. Urethra-Sparing, Intraoperative, Real-Time Planned, Permanent-Seed Prostate Brachytherapy: Toxicity Analysis

    SciTech Connect

    Zilli, Thomas; Taussky, Daniel; Donath, David; Le, Hoa Phong; Larouche, Renee-Xaviere; Beliveau-Nadeau, Dominique; Hervieux, Yannick; Delouya, Guila

    2011-11-15

    Purpose: To report the toxicity outcome in patients with localized prostate cancer undergoing {sup 125}I permanent-seed brachytherapy (BT) according to a urethra-sparing, intraoperative (IO), real-time planned conformal technique. Methods and Materials: Data were analyzed on 250 patients treated consecutively for low- or intermediate-risk prostate cancer between 2005 and 2009. The planned goal was urethral V{sub 150} = 0. Acute and late genitourinary (GU), gastrointestinal (GI), and erectile toxicities were scored with the International Prostate Symptom Score (IPSS) questionnaire and Common Terminology Criteria for Adverse Events (version 3.0). Median follow-up time for patients with at least 2 years of follow-up (n = 130) was 34.4 months (range, 24-56.9 months). Results: Mean IO urethra V{sub 150} was 0.018% {+-} 0.08%. Mean prostate D{sub 90} and V{sub 100} on day-30 computed tomography scan were 158.0 {+-} 27.0 Gy and 92.1% {+-} 7.2%, respectively. Mean IPSS peak was 9.5 {+-} 6.3 1 month after BT (mean difference from baseline IPSS, 5.3). No acute GI toxicity was observed in 86.8% of patients. The 3-year probability of Grade {>=}2 late GU toxicity-free survival was 77.4% {+-} 4.0%, with Grade 3 late GU toxicity encountered in only 3 patients. Three-year Grade 1 late GI toxicity-free survival was 86.1% {+-} 3.2%. No patient presented Grade {>=}2 late GI toxicity. Of patients with normal sexual status at baseline, 20.7% manifested Grade {>=}2 erectile dysfunction after BT. On multivariate analysis, elevated baseline IPSS (p = 0.016) and high-activity sources (median 0.61 mCi) (p = 0.033) predicted increased Grade {>=}2 late GU toxicity. Conclusions: Urethra-sparing IO BT results in low acute and late GU toxicity compared with the literature. High seed activity and elevated IPSS at baseline increased long-term GU toxicity.

  8. Isotope and Patient Age Predict for PSA Spikes After Permanent Prostate Brachytherapy

    SciTech Connect

    Bostancic, Chelsea; Merrick, Gregory S. . E-mail: gmerrick@urologicresearchinstitute.org; Butler, Wayne M.; Wallner, Kent E.; Allen, Zachariah; Galbreath, Robert; Lief, Jonathan; Gutman, Sarah E.

    2007-08-01

    Purpose: To evaluate prostate-specific antigen (PSA) spikes after permanent prostate brachytherapy in low-risk patients. Methods and Materials: The study population consisted of 164 prostate cancer patients who were part of a prospective randomized trial comparing {sup 103}Pd and {sup 125}I for low-risk disease. Of the 164 patients, 61 (37.2%) received short-course androgen deprivation therapy. The median follow-up was 5.4 years. On average, 11.1 post-treatment PSA measurements were obtained per patient. Biochemical disease-free survival was defined as a PSA level of {<=}0.40 ng/mL after nadir. A PSA spike was defined as an increase of {>=}0.2 ng/mL, followed by a durable decline to prespike levels. Multiple parameters were evaluated as predictors for a PSA spike. Results: Of the 164 patients, 44 (26.9%) developed a PSA spike. Of the 46 hormone-naive {sup 125}I patients and 57 hormone-naive {sup 103}Pd patients, 21 (45.7%) and 8 (14.0%) developed a PSA spike. In the hormone-naive patients, the mean time between implantation and the spike was 22.6 months and 18.7 months for {sup 125}I and {sup 103}Pd, respectively. In patients receiving neoadjuvant androgen deprivation therapy, the incidence of spikes was comparable between isotopes ({sup 125}I 28.1% and {sup 103}Pd 20.7%). The incidence of spikes was substantially different in patients <65 years vs. {>=}65 years old (38.5% vs. 16.3%). On multivariate Cox regression analysis, patient age (p < 0.001) and isotope (p = 0.002) were significant predictors for spike. Conclusion: In low-risk prostate cancer, PSA spikes are most common in patients implanted with {sup 125}I and/or <65 years of age. Differences in isotope-related spikes are most pronounced in hormone-naive patients.

  9. Iodine-125 implant and external beam irradiation in patients with localized pancreatic carcinoma. [Efficacy and complications

    SciTech Connect

    Shipley, W.U.; Nardi, G.L.; Cohen, A.M.; Ling, C.C.

    1980-02-15

    Twelve patients with biopsy-proven clinically localized ductal pancreatic cancers (less than 7 cm in greatest diameter) judged unsuitable for resection were treated by bypass surgery, an Iodine-125 implant (20 to 39 mCi), and postoperative irradiation (4000 to 4500 rads). The potential problems of significant bleeding, pancreatic fistula, or pancreatitis were not experienced. A local recurrence developed in one patient and two recurred in regional lymph nodes. The projected median survival of the group is 11 months with four of the 12 patients still surviving. For purposes of comparison all patients with pancreatic ductal carcinoma treated by radical resection during a similar time were evaluated. All ten have died with a median survival of six months. Twelve of 22 (55%) of the combined implanted and resected groups have developed distant metastasis. Further pursuit of intraoperative techniques of irradiation in combination with adjuvant multidrug chemotherapy seems indicated in an attempt to prolong patient survival which is now limited by hematogenous metastases.

  10. Brachytherapy optimization using radiobiological-based planning for high dose rate and permanent implants for prostate cancer treatment

    NASA Astrophysics Data System (ADS)

    Seeley, Kaelyn; Cunha, J. Adam; Hong, Tae Min

    2017-01-01

    We discuss an improvement in brachytherapy--a prostate cancer treatment method that directly places radioactive seeds inside target cancerous regions--by optimizing the current standard for delivering dose. Currently, the seeds' spatiotemporal placement is determined by optimizing the dose based on a set of physical, user-defined constraints. One particular approach is the ``inverse planning'' algorithms that allow for tightly fit isodose lines around the target volumes in order to reduce dose to the patient's organs at risk. However, these dose distributions are typically computed assuming the same biological response to radiation for different types of tissues. In our work, we consider radiobiological parameters to account for the differences in the individual sensitivities and responses to radiation for tissues surrounding the target. Among the benefits are a more accurate toxicity rate and more coverage to target regions for planning high-dose-rate treatments as well as permanent implants.

  11. Permanent Prostate Brachytherapy in Prostate Glands <20 cm{sup 3}

    SciTech Connect

    Mayadev, Jyoti; Merrick, Gregory S.; Reed, Joshua R.; Butler, Wayne M.; Galbreath, Robert W.; Allen, Zachariah A.; Wallner, Kent E.

    2010-04-15

    Purpose: To investigate the dosimetry, treatment-related morbidity, and biochemical outcomes for brachytherapy in patients with prostate glands <20 cm{sup 3}. Methods and Materials: From November 1996 to October 2006, 104 patients with prostate glands <20 cm{sup 3} underwent brachytherapy. Multiple prostate, urethral, and rectal dosimetric parameters were evaluated. Treatment-related urinary and rectal morbidity were assessed from patient questionnaires. Cause-specific survival, biochemical progression-free survival, and overall survival were recorded. Results: The median patient age, follow up, and pre-treatment ultrasound volume was 64 years, 5.0 years and 17.6cm{sup 3}, respectively. Median day 0 dosimetry was significant for the following: V100 98.5%, D90 126.1% and R100 <0.5% of prescription dose. The mean urethral and maximum urethral doses were 119.6% and 133.8% of prescription. The median time to International Prostate Symptom Score resolution was 4 months. There were no RTOG grade III or IV rectal complications. The cause-specific survival, biochemical progression-free survival, and overall survival rates were 100%, 92.5%, and 77.8% at 9 years. For biochemically disease-free patients, the median most recent postbrachytherapy PSA value was 0.02 ng/mL. Conclusion: Our results demonstrate that brachytherapy for small prostate glands is highly effective, with an acceptable morbidity profile, excellent postimplant dosimetry, acceptable treatment-related morbidity, and favorable biochemical outcomes.

  12. Method for the simultaneous preparation of Radon-211, Xenon-125, Xenon-123, Astatine-211, Iodine-125 and Iodine-123

    DOEpatents

    Mirzadeh, Saed; Lambrecht, Richard M.

    1987-01-01

    A method for simultaneously preparing Radon-211, Astatine-211, Xenon-125, Xenon-123, Iodine-125 and Iodine-123 in a process that includes irradiating a fertile metal material then using a one-step chemical procedure to collect a first mixture of about equal amounts of Radon-211 and Xenon-125, and a separate second mixture of about equal amounts of Iodine-123 and Astatine-211.

  13. The use of iodine-125 seeds as a substitute for iridium-192 seeds in temporary interstitial breast implants

    SciTech Connect

    Vicini, F.; White, J.; Gustafson, G.; Matter, R.C.; Edmundson, G.; Martinez, A.; Clarke, D.H.

    1993-10-20

    We have previously reported that the use of iodine-125 seeds in temporary plastic tube interstitial implants may be more advantageous than iridium-192 seeds due to less patient and personnel radiation exposure, reduced shielding requirements, and significant dosimetric advantages. The impact of this isotope on the rate of local control and cosmetic outcome in patients with early stage breast cancer treated with interstitial implants for their irradiation {open_quotes}boost{close_quotes} remains to be defined. We reviewed the treatment outcome of 402 consecutive cases of Stage I and II breast cancer undergoing breast conserving therapy between 1/1/80 and 12/31/87. All patients underwent excisional biopsy and received 45-50 Gy to the entire breast followed by a boost to the tumor bed using either electrons (104 patients), photons (15 patients), or an interstitial implant with either iridium-192 (197 patients) or iodine-125 (86 patients) to at least 60 Gy. Iodine-125 implants were primarily performed in patients with significant risk factors for local recurrence (71%) or in patients with large breasts (17%). Local tumor control and cosmetic outcome were assessed and contrasted between patients boosted with each modality. We conclude that patients with State I and II breast cancer undergoing breast conserving therapy and judged to be candidates for boosts with interstitial implants can be effectively treated with iodine-125 seeds. Use of the isotope results in less patient and personnel irradiation exposure and a better dose distribution than iridium-192, since dose optimization can be routinely employed. Overall, local control and cosmetic outcome have been excellent and are similar to either iridium-192, electrons, or photons. 21 refs., 4 tabs.

  14. SU-F-BRA-03: Integrating Novel Electromagnetic Tracking Hollow Needle Assistance in Permanent Implant Brachytherapy Procedures

    SciTech Connect

    Racine, E; Hautvast, G; Binnekamp, D; Beaulieu, L

    2015-06-15

    Purpose: To report on the results of a complete permanent implant brachytherapy procedure assisted by an electromagnetic (EM) hollow needle possessing both 3D tracking and seed drop detection abilities. Methods: End-to-end in-phantom EM-assisted LDR procedures were conducted. The novel system consisted of an EM tracking apparatus (NDI Aurora V2, Planar Field Generator), a 3D US scanner (Philips CX50), a hollow needle prototype allowing 3D tracking and seed drop detection and a specially designed treatment planning software (Philips Healthcare). A tungsten-doped 30 cc spherical agarose prostate immersed in gelatin was used for the treatment. A cylindrical shape of 0.8 cc was carved along its diameter to mimic the urethra. An initial plan of 26 needles and 47 seeds was established with the system. The plan was delivered with the EM-tracked hollow needle, and individual seed drop locations were recorded on the fly. The phantom was subsequently imaged with a CT scanner from which seed positions and contour definitions were obtained. The DVHs were then independently recomputed and compared with those produced by the planning system, both before and after the treatment. Results: Of the 47 seeds, 45 (96%) were detected by the EM technology embedded in the hollow needle design. The executed plan (from CT analysis) differed from the initial plan by 2%, 14% and 8% respectively in terms of V100, D90 and V150 for the prostate, and by 8%, 7% and 10% respectively in terms of D5, V100 and V120 for the urethra. Conclusion: The average DVH deviations between initial and executed plans were within a 5% tolerance imposed for this proof-of-concept assessment. This relatively good concordance demonstrates the feasibility and potential benefits of combining EM tracking and seed drop detection for real-time dosimetry validation and assistance in permanent implant brachytherapy procedures. This project has been entirely funded by Philips Healthcare.

  15. Distant Metastases Following Permanent Interstitial Brachytherapy for Patients With Clinically Localized Prostate Cancer

    SciTech Connect

    Taira, Al V.; Merrick, Gregory S.; Galbreath, Robert W.; Butler, Wayne M.; Lief, Jonathan; Adamovich, Edward; Wallner, Kent E.

    2012-02-01

    Purpose: Recent publications have suggested high-risk patients undergoing radical prostatectomy have a lower risk of distant metastases and improved cause-specific survival (CSS) than patients receiving definitive external beam radiation therapy (XRT). To date, none of these studies has compared distant metastases and CSS in brachytherapy patients. In this study, we evaluate such parameters in a consecutive cohort of brachytherapy patients. Methods and Materials: From April 1995 to June 2007, 1,840 consecutive patients with clinically localized prostate cancer were treated with brachytherapy. Risk groups were stratified according to National Comprehensive Cancer Network ( (www.nccn.org)) guidelines. Subgroups of 658, 893, and 289 patients were assigned to low, intermediate, and high-risk categories. Median follow-up was 7.2 years. Along with brachytherapy implantation, 901 (49.0%) patients received supplemental XRT, and 670 (36.4%) patients received androgen deprivation therapy (median duration, 4 months). The mode of failure (biochemical, local, or distant) was determined for each patient for whom therapy failed. Cause of death was determined for each deceased patient. Multiple parameters were evaluated for impact on outcome. Results: For the entire cohort, metastases-free survival (MFS) and CSS at 12 years were 98.1% and 98.2%, respectively. When rates were stratified by low, intermediate, and high-risk groups, the 12-year MFS was 99.8%, 98.1%, and 93.8% (p < 0.001), respectively. CSS rates were 99.8%, 98.0%, and 95.3% (p < 0.001) for low, intermediate, and high-risk groups, respectively. Biochemical progression-free survival was 98.7%, 95.9% and 90.4% for low, intermediate, and high-risk patients, respectively (p < 0.001). In multivariate Cox-regression analysis, MFS was mostly closely related to Gleason score and year of treatment, whereas CSS was most closely associated with Gleason score. Conclusions: Excellent CSS and MFS rates are achievable with high

  16. Iodine-125-labeled cRGD-gold nanoparticles as tumor-targeted radiosensitizer and imaging agent

    NASA Astrophysics Data System (ADS)

    Su, Ning; Dang, Yajie; Liang, Guangli; Liu, Guizhi

    2015-04-01

    Research interests on radiosensitive property of gold nanoparticles (GNPs) are rapidly raised because of the extensively proved in vitro effectiveness and clinical necessity. However, the issue of targeted accumulation of GNPs in tumor tissues hindered the transference to in vivo applications. In this study, hybrid nano-sized cyclic Arg-Gly-Asp-conjugated GNPs (cRGD-GNPs) integrated with radioactive iodine-125 was fabricated as tumor-targeted radiosensitizer. Therapeutic effects, including acute apoptosis (2 days post treatment) and long-term influence (up to 21 days), were investigated on NCI-H446 tumor-bearing mice via Tc-99 m-Annexin V SPECT and volume measurements, respectively. Apoptosis and volume loss were consistent in showing that tumor growth was effectively suppressed via the treatment of 125I-cRGD-GNP sensitized radiotherapy (RT), a more significantly radiosensitive effect than the treatment of non-targeted GNPs with RT, RT treatment alone, and no treatment. SPECT/CT images showed that the uptake of cRGD-GNPs by tumor tissues reached the peak target/non-target value of 4.76 at around 2 h post injection, and dynamic radioactivity monitoring showed that 125I-cRGD-GNPs maintained about 2.5% of injected dosage at 55 h post injection. For long-term influence, a significant radiosensitized RT-induced volume loss was observed. Hence, cyclic RGD conjugation makes the GNP-based radiosensitizer tumor targeting, offering a new modality for enhancing radiotherapeutic efficacy. Additionally, the introduction of I-125 serves as both a therapeutic factor and a radiotracer for in vivo tracking of GNPs.

  17. Continuous Low-dose-rate Irradiation of Iodine-125 Seeds Inhibiting Perineural Invasion in Pancreatic Cancer

    PubMed Central

    Lu, Zheng; Dong, Teng-Hui; Si, Pei-Ren; Shen, Wei; Bi, Yi-Liang; Min, Min; Chen, Xin; Liu, Yan

    2016-01-01

    Background: Perineural invasion (PNI) is a histopathological characteristic of pancreatic cancer (PanCa). The aim of this study was to observe the treatment effect of continuous low-dose-rate (CLDR) irradiation to PNI and assess the PNI-related pain relief caused by iodine-125 (125I) seed implantation. Methods: The in vitro PNI model established by co-culture with dorsal root ganglion (DRG) and cancer cells was interfered under 2 and 4 Gy of 125I seeds CLDR irradiation. The orthotopic models of PNI were established, and 125I seeds were implanted in tumor. The PNI-related molecules were analyzed. In 30 patients with panCa, the pain relief was assessed using a visual analog scale (VAS). Pain intensity was measured before and 1 week, 2 weeks, and 1, 3, and 6 months after 125I seed implantation. Results: The co-culture of DRG and PanCa cells could promote the growth of PanCa cells and DRG neurites. In co-culture groups, the increased number of DRG neurites and pancreatic cells in radiation group was significantly less. In orthotopic models, the PNI-positive rate in radiation and control group was 3/11 and 7/11; meanwhile, the degrees of PNI between radiation and control groups was significant difference (P < 0.05). At week 2, the mean VAS pain score in patients decreased by 50% and significantly improved than the score at baseline (P < 0.05). The pain scores were lower in all patients, and the pain-relieving effect was retained about 3 months. Conclusions: The CLDR irradiation could inhibit PNI of PanCa with the value of further study. The CLDR irradiation could do great favor in preventing local recurrence and alleviating pain. PMID:27748339

  18. Source strength assay of iodine-125 seeds sealed within sterile packaging.

    PubMed

    Otani, Yuki; Yamada, Takahiro; Kato, Shingo; Shikama, Naoto; Funakoshi, Kazuto; Kuroda, Isao; Numasaki, Hodaka; Nose, Takayuki; Dokiya, Takushi; Oguchi, Masahiko

    2013-03-04

    Early-stage prostate cancer is widely treated by iodine-125 (I-125) seed implantation. While quality assurance methods are in place to assure consistency in I-125 seed source strength, current methods involve the breaking of the sterilization package, raising issues concerning sterility and time limitations. The purpose of this study was to develop a method of characterizing the total source strength of I-125 seeds within a cartridge that has been sealed within a sterilization package and to evaluate the probability of detecting an out-of-calibration seed (aberrant seed). We defined a protocol to determine the ability of a well-type ionization chamber to detect aberrant I-125 seeds within a cartridge sealed in the sterilization package. A novel jig for a well-type ionization chamber was designed to accommodate the sterilization package. One seed was chosen randomly from two cartridges containing five or 15 seeds (0.544 U source strength) and was exchanged with aberrant seeds of six different source strengths. The source strength was measured at each position within the cartridge. The results indicated that the response of the well chamber was sensitive to changes in the aberrant seed position within the cartridge and the source strength of the aberrant seed. The correlation coefficient between single seed and batch assay results was high (0.998). A novel jig and a measurement method using a well ionization chamber were developed, which allowed for a batch assay characterization of the total source strength of I-125 seeds within a cartridge sealed within sterilization package. This method is simple, time-saving, and offers greater practical application.

  19. Evaluation of dosimetry and excess seeds in permanent brachytherapy using a modified hybrid method: a single-institution experience.

    PubMed

    Kobayashi, Kana; Okihara, Koji; Iwata, Tsuyoshi; Aibe, Norihiro; Kodani, Naohiro; Tsubokura, Takuji; Kamoi, Kazumi; Miki, Tsuneharu; Yamazaki, Hideya

    2013-05-01

    Permanent prostate brachytherapy is frequently performed worldwide, and many studies have demonstrated its favorable outcomes. Implant seeds used in this procedure contain a precise amount of radionuclide and are completely sealed. Because these seeds are not manufactured in Japan, they are expensive (6300 yen per seed) and therefore need careful management as a radioisotope. The proper implantation technique requires considerable procedure time, good dosimetric outcomes and simple radioactive isotope management. To evaluate the modified hybrid interactive technique based on these considerations, we assessed 313 patients who underwent hybrid interactive brachytherapy without additional external beam radiotherapy. We evaluated the duration of the procedure, dosimetric factors and the total number of excess seeds. The dosimetric results from computed tomography on Day 30 of follow-up were: 172 Gy (range 130-194 Gy) for pD90, 97.8% (83.5-100%) for pV100, 54.6% (27.5-82.4%) for pV150, 164 Gy (120-220 Gy) for uD90, 194 Gy (126-245 Gy) for uD30, 210 Gy (156-290 Gy) for uD5, 0.02 ml (0-1.2 ml) for rV100 and 0 ml (0-0.2 ml) for rV150. The number of excess seeds was determined by subtracting the number of implanted seeds from the expected number of seeds calculated from previously proposed nomograms. As per our method, nine excess seeds were used for two patients, whereas using the nomograms, the number of excess seeds was approximately eight per patient. Our modified hybrid interactive technique reduced the number of excess seeds while maintaining treatment quality.

  20. Natural History of Clinically Staged Low- and Intermediate-Risk Prostate Cancer Treated With Monotherapeutic Permanent Interstitial Brachytherapy

    SciTech Connect

    Taira, Al V.; Merrick, Gregory S.; Galbreath, Robert W.; Wallner, Kent E.; Butler, Wayne M.

    2010-02-01

    Purpose: To evaluate the natural history of clinically staged low- and intermediate-risk prostate cancer treated with permanent interstitial seed implants as monotherapy. Methods and Materials: Between April 1995 and May 2005, 463 patients with clinically localized prostate cancer underwent brachytherapy as the sole definitive treatment. Men who received supplemental external beam radiotherapy or androgen deprivation therapy were excluded. Dosimetric implant quality was determined based on the minimum dose that covered 90% of the target volume and the volume of the prostate gland receiving 100% of the prescribed dose. Multiple parameters were evaluated as predictors of treatment outcomes. Results: The 12-year biochemical progression-free survival (bPFS), cause-specific survival, and overall survival rates for the entire cohort were 97.1%, 99.7%, and 75.4%, respectively. Only pretreatment prostate-specific antigen level, percent positive biopsy cores, and minimum dose that covered 90% of the target volume were significant predictors of biochemical recurrence. The bPFS, cause-specific survival, and overall survival rates were 97.4%, 99.6%, and 76.2%, respectively, for low-risk patients and 96.4%, 100%, and 74.0%, respectively, for intermediate-risk patients. The bPFS rate was 98.8% for low-risk patients with high-quality implants versus 92.1% for those with less adequate implants (p < 0.01), and it was 98.3% for intermediate-risk patients with high-quality implants versus 86.4% for those with less adequate implants (p < 0.01). Conclusions: High-quality brachytherapy implants as monotherapy can provide excellent outcomes for men with clinically staged low- and intermediate-risk prostate cancer. For these men, a high-quality implant can achieve results comparable to high-quality surgery in the most favorable pathologically staged patient subgroups.

  1. In vitro comparative study of vibro-acoustography versus pulse-echo ultrasound in imaging permanent prostate brachytherapy seeds

    PubMed Central

    Mitri, F.G.; Davis, B.J.; Greenleaf, J.F.; Fatemi, M.

    2010-01-01

    Background Permanent prostate brachytherapy (PPB) is a common treatment for early stage prostate cancer. While the modern approach using trans-rectal ultrasound guidance has demonstrated excellent outcome, the efficacy of PPB depends on achieving complete radiation dose coverage of the prostate by obtaining a proper radiation source (seed) distribution. Currently, brachytherapy seed placement is guided by trans-rectal ultrasound imaging and fluoroscopy. A significant percentage of seeds are not detected by trans-rectal ultrasound because certain seed orientations are invisible making accurate intra-operative feedback of radiation dosimetry very difficult, if not impossible. Therefore, intra-operative correction of suboptimal seed distributions cannot easily be done with current methods. Vibro-acoustography (VA) is an imaging modality that is capable of imaging solids at any orientation, and the resulting images are speckle free. Objective and methods The purpose of this study is to compare the capabilities of VA and pulse-echo ultrasound in imaging PPB seeds at various angles and show the sensitivity of detection to seed orientation. In the VA experiment, two intersecting ultrasound beams driven at f1 = 3.00 MHz and f2 = 3.020 MHz respectively were focused on the seeds attached to a latex membrane while the amplitude of the acoustic emission produced at the difference frequency 20 kHz was detected by a low frequency hydrophone. Results Finite element simulations and results of experiments conducted under well-controlled conditions in a water tank on a series of seeds indicate that the seeds can be detected at any orientation with VA, whereas pulse-echo ultrasound is very sensitive to the seed orientation. Conclusion It is concluded that vibro-acoustography is superior to pulse-echo ultrasound for detection of PPB seeds. PMID:18538365

  2. Metallic artifact mitigation and organ-constrained tissue assignment for Monte Carlo calculations of permanent implant lung brachytherapy.

    PubMed

    Sutherland, J G H; Miksys, N; Furutani, K M; Thomson, R M

    2014-01-01

    in generated phantoms, this erroneous assignment is reduced, generally resulting in higher doses. Lung-constrained tissue assignment also results in increased doses in regions of interest due to a reduction in the erroneous assignment of adipose to voxels within lung contours. Differences in dose metrics calculated for different computational phantoms are sensitive to radionuclide photon spectra with the largest differences for (103)Pd seeds and smallest but still considerable differences for (131)Cs seeds. Despite producing differences in CT images, dose metrics calculated using the STR, fan beam + STR, and 3D median filter techniques produce similar dose metrics. Results suggest that the accuracy of dose distributions for permanent implant lung brachytherapy is improved by applying lung-constrained tissue assignment schemes to metallic artifact corrected images.

  3. Metallic artifact mitigation and organ-constrained tissue assignment for Monte Carlo calculations of permanent implant lung brachytherapy

    SciTech Connect

    Sutherland, J. G. H.; Miksys, N.; Thomson, R. M.; Furutani, K. M.

    2014-01-15

    assignment within lung contours are employed in generated phantoms, this erroneous assignment is reduced, generally resulting in higher doses. Lung-constrained tissue assignment also results in increased doses in regions of interest due to a reduction in the erroneous assignment of adipose to voxels within lung contours. Differences in dose metrics calculated for different computational phantoms are sensitive to radionuclide photon spectra with the largest differences for{sup 103}Pd seeds and smallest but still considerable differences for {sup 131}Cs seeds. Conclusions: Despite producing differences in CT images, dose metrics calculated using the STR, fan beam + STR, and 3D median filter techniques produce similar dose metrics. Results suggest that the accuracy of dose distributions for permanent implant lung brachytherapy is improved by applying lung-constrained tissue assignment schemes to metallic artifact corrected images.

  4. Metallic artifact mitigation and organ-constrained tissue assignment for Monte Carlo calculations of permanent implant lung brachytherapy

    SciTech Connect

    Sutherland, J. G. H.; Miksys, N.; Thomson, R. M.; Furutani, K. M.

    2014-01-15

    assignment within lung contours are employed in generated phantoms, this erroneous assignment is reduced, generally resulting in higher doses. Lung-constrained tissue assignment also results in increased doses in regions of interest due to a reduction in the erroneous assignment of adipose to voxels within lung contours. Differences in dose metrics calculated for different computational phantoms are sensitive to radionuclide photon spectra with the largest differences for{sup 103}Pd seeds and smallest but still considerable differences for {sup 131}Cs seeds. Conclusions: Despite producing differences in CT images, dose metrics calculated using the STR, fan beam + STR, and 3D median filter techniques produce similar dose metrics. Results suggest that the accuracy of dose distributions for permanent implant lung brachytherapy is improved by applying lung-constrained tissue assignment schemes to metallic artifact corrected images.

  5. DNA and RNA folds in transcription complex as evidenced by iodine-125 radioprobing.

    PubMed

    Karamychev, V N; Panyutin, I G; Neumann, R D; Zhurkin, V B

    2000-01-01

    Abstract Folding of the DNA and RNA strands in an arrested T7 RNA polymerase (RNAP) transcription complex was studied by radioprobing, a novel method based on an analysis of the strand breaks produced by decay of the iodine-125 incorporated at the C5 position of cytosine. (125)I-labeled cytosines were incorporated into transcripts at different positions relative to the site of the arrest. The intensities of the DNA breaks inversely correlate with the distances from the (125)I decay site, so the radioprobing data provide information about the spatial RNA/DNA folding during transcription. We found that the yield of DNA strand breaks is significantly higher in the template than the non-template strand. This is consistent with local opening of the DNA duplex and formation of a hybrid between RNA and the template DNA strand. Our data demonstrate that the RNA-DNA hybrid has a nonuni form A-like structure. When the (125)I is incorporatedseven nucleotides from the active center of RNAP, the yield of strand breaks is substantially lower than if (125)I is positioned at the ends of the hybrid. Consequently, the DNA and RNA strands are located closer to each other at the ends of the hybrid and somehow separated in the middle. Surprisingly, the (125)I-induced breaks were detected in both DNA strands upstream from the transcription "bubble" indicating that DNA and RNA are closely associated outside the RNAP cleft. Thus, radioprobing data imply that the RNA/DNA fold in the complex with T7 RNAP is more complicated than had been anticipated by the existing models. Based on the present data, we suggest a sterically feasible model explaining how formation of the long RNA-DNA hybrid can result in the initiation-to-elongation switch in the T7 transcription complex. According to this model, the topological linkage between the DNA and RNA strands provides the necessary stability for the elongation complex, while permitting movement of the polymerase along the DNA duplex.

  6. Impact of prostate edema on cell survival and tumor control after permanent interstitial brachytherapy for early stage prostate cancers

    PubMed Central

    Chen, Zhe (Jay); Roberts, Kenneth; Decker, Roy; Pathare, Pradip; Rockwell, Sara; Nath, Ravinder

    2011-01-01

    Previous studies have shown that the procedure-induced prostate edema during permanent interstitial brachytherapy (PIB) can cause significant variations in the dose delivered to the prostate gland. Because the clinical impact of edema-induced dose variations depends strongly on the magnitude of the edema, the temporal pattern of its resolution and its interplay with the decay of radioactivity and the underlying biological processes of tumor cells (such as tumor potential doubling time), we investigated the impact of edema-induced dose variations on the tumor cell survival and tumor control probability after PIB with the 131Cs, 125I and 103Pd sources used in current clinical practice. The exponential edema resolution model reported by Waterman et al. (Int. J. Radiat. Oncol. Biol. Phys. 41, 1069–1077–1998) was used to characterize the edema evolutions observed previously during clinical PIB for prostate cancer. The concept of biologically effective dose (BED), taking into account tumor cell proliferation and sublethal damage repair during dose delivery, was used to characterize the effects of prostate edema on cell survival and tumor control probability. Our calculation indicated that prostate edema, if not taken into account appropriately, can increase the cell survival and decrease the probability of local control of PIB. The edema-induced increase in cell survival increased with increasing edema severity, decreasing half-life for radioactive decay and decreasing energy of the photons energy emitted by the source. At the doses currently prescribed for PIB and for prostate cancer cells characterized by nominal radiobiology parameters recommended by AAPM TG-137, PIB using 125I sources was less affected by edema than PIB using 131Cs or 103Pd sources due to the long radioactive decay half-life of 125I. The effect of edema on PIB using 131Cs or 103Pd was similar. The effect of edema on 103Pd PIB was slightly greater, even though the decay half-life of 103Pd (17 days

  7. The impact of prostate edema on cell survival and tumor control after permanent interstitial brachytherapy for early stage prostate cancers

    NASA Astrophysics Data System (ADS)

    (Jay Chen, Zhe; Roberts, Kenneth; Decker, Roy; Pathare, Pradip; Rockwell, Sara; Nath, Ravinder

    2011-08-01

    Previous studies have shown that procedure-induced prostate edema during permanent interstitial brachytherapy (PIB) can cause significant variations in the dose delivered to the prostate gland. Because the clinical impact of edema-induced dose variations strongly depends on the magnitude of the edema, the temporal pattern of its resolution and its interplay with the decay of radioactivity and the underlying biological processes of tumor cells (such as tumor potential doubling time), we investigated the impact of edema-induced dose variations on the tumor cell survival and tumor control probability after PIB with the 131Cs, 125I and 103Pd sources used in current clinical practice. The exponential edema resolution model reported by Waterman et al (1998 Int. J. Radiat. Oncol. Biol. Phys. 41 1069-77) was used to characterize the edema evolutions previously observed during clinical PIB for prostate cancer. The concept of biologically effective dose, taking into account tumor cell proliferation and sublethal damage repair during dose delivery, was used to characterize the effects of prostate edema on cell survival and tumor control probability. Our calculation indicated that prostate edema, if not appropriately taken into account, can increase the cell survival and decrease the probability of local control of PIB. The magnitude of an edema-induced increase in cell survival increased with increasing edema severity, decreasing half-life of radioactive decay and decreasing photon energy emitted by the source. At the doses currently prescribed for PIB and for prostate cancer cells characterized by nominal radiobiology parameters recommended by AAPM TG-137, PIB using 125I sources was less affected by edema than PIB using 131Cs or 103Pd sources due to the long radioactive decay half-life of 125I. The effect of edema on PIB using 131Cs or 103Pd was similar. The effect of edema on 103Pd PIB was slightly greater, even though the decay half-life of 103Pd (17 days) is longer than

  8. Preoperative treatment planning with intraoperative optimization can achieve consistent high-quality implants in prostate brachytherapy

    SciTech Connect

    Kudchadker, Rajat J.; Pugh, Thomas J.; Swanson, David A.; Bruno, Teresa L.; Bolukbasi, Yasemin; Frank, Steven J.

    2012-01-01

    Advances in brachytherapy treatment planning systems have allowed the opportunity for brachytherapy to be planned intraoperatively as well as preoperatively. The relative advantages and disadvantages of each approach have been the subject of extensive debate, and some contend that the intraoperative approach is vital to the delivery of optimal therapy. The purpose of this study was to determine whether high-quality permanent prostate implants can be achieved consistently using a preoperative planning approach that allows for, but does not necessitate, intraoperative optimization. To achieve this purpose, we reviewed the records of 100 men with intermediate-risk prostate cancer who had been prospectively treated with brachytherapy monotherapy between 2006 and 2009 at our institution. All patients were treated with iodine-125 stranded seeds; the planned target dose was 145 Gy. Only 8 patients required adjustments to the plan on the basis of intraoperative findings. Consistency and quality were assessed by calculating the correlation coefficient between the planned and implanted amounts of radioactivity and by examining the mean values of the dosimetric parameters obtained on preoperative and 30 days postoperative treatment planning. The amount of radioactivity implanted was essentially identical to that planned (mean planned radioactivity, 41.27 U vs. mean delivered radioactivity, 41.36 U; R{sup 2} = 0.99). The mean planned and day 30 prostate V100 values were 99.9% and 98.6%, respectively. The mean planned and day 30 prostate D90 values were 186.3 and 185.1 Gy, respectively. Consistent, high-quality prostate brachytherapy treatment plans can be achieved using a preoperative planning approach, mostly without the need for intraoperative optimization. Good quality assurance measures during simulation, treatment planning, implantation, and postimplant evaluation are paramount for achieving a high level of quality and consistency.

  9. Chemisorption of iodine-125 to gold nanoparticles allows for real-time quantitation and potential use in nanomedicine

    NASA Astrophysics Data System (ADS)

    Walsh, Adrian A.

    2017-04-01

    Gold nanoparticles have been available for many years as a research tool in the life sciences due to their electron density and optical properties. New applications are continually being developed, particularly in nanomedicine. One drawback is the need for an easy, real-time quantitation method for gold nanoparticles so that the effects observed in in vitro cell toxicity assays and cell uptake studies can be interpreted quantitatively in terms of nanoparticle loading. One potential method of quantifying gold nanoparticles in real time is by chemisorption of iodine-125, a gamma emitter, to the nanoparticles. This paper revisits the labelling of gold nanoparticles with iodine-125, first described 30 years ago and never fully exploited since. We explore the chemical properties and usefulness in quantifying bio-functionalised gold nanoparticle binding in a quick and simple manner. The gold particles were labelled specifically and quantitatively simply by mixing the two items. The nature of the labelling is chemisorption and is robust, remaining bound over several weeks in a variety of cell culture media. Chemisorption was confirmed as potassium iodide can remove the label whereas sodium chloride and many other buffers had no effect. Particles precoated in polymers or proteins can be labelled just as efficiently allowing for post-labelling experiments in situ rather than using radioactive gold atoms in the production process. We also demonstrate that interparticle exchange of I-125 between different size particles does not appear to take place confirming the affinity of the binding.

  10. Influence of administered indigenous microorganisms on uptake of (iodine-125). gamma. -globulin in vivo by intestinal segments of neonatal calves

    SciTech Connect

    James, R.E.; Polan, C.E.; Cummins, K.A.

    1981-01-01

    Ten calves less than 14 h of age (average 8.6 h) were anaesthetized, and the intestine was ligated into segments 10 cm in length at 3-cm intervals beginning 1.8 m anterior to the ileocecal junction and proceeding proximally. Seven treatments were assigned in random order to segments in three successive sections of the small intestine. Segments received 1 ml of viable bacteria of intestinal origin, autoclaved bacteria of intestinal origin, or sterile microbiological broth at zero time; then after 4 h they were injected with iodine-125 labeled ..gamma..-globulin. After an additional 1.5 h, the experiment was ended and uptake assayed. Two treatments measured anaerobic microbial growth after 4 h incubation with 1 ml of either sterile broth or live bacteria culture. Residual (iodine-125) ..gamma..-globulin was measured in segments receiving 1 ml of sterile broth or live bacteria culture with 5.5-h incubation followed by 15-s exposure to labeled ..gamma..-globulin. Uptake was lowest in segments receiving live bacteria as compared to segments receiving sterile inocula. Number of bacteria per gram of tissue was correlated negatively with uptake. Low corticosteroids in serum were associated with low uptake of ..gamma..-globulin.

  11. Interactive tool for visualization and segmentation of permanent radioactive seeds in postoperative prostate brachytherapy CT images

    NASA Astrophysics Data System (ADS)

    Pathak, Sayan D.; Stoknes, Kevin; Grimm, Peter D.; Estlund, Jacque; Chalana, Vikram; Kim, Yongmin

    1999-05-01

    Implantation of radioactive isotopes within the prostate for the treatment of early stage localized prostate cancer is becoming a popular treatment option. Postoperative calculation of the dose delivered to the prostate requires accurate verification of the number and location of seeds within the prostate. Current post operative dosimetry technique requires the dosimetrist to manually count and record the position of each seed from x-ray computed tomography (CT) images. This procedure is operator-dependent and time-consuming, thus limiting the ability of different brachytherapy centers to compare results and create a standard methodology. Seed identification is performed by thresholding the CT images interactively, using a graphical user interface, followed by mathematical morphology to remove noise. Segmented seeds are grouped into regions via connected-component analysis. Regions are then classified into seeds using a prior knowledge of the seed dimensions and their relative positions in the consecutive CT images. Unresolved regions, which can indicate the presence of more than one seed, are corrected manually. The efficiency of this tool was evaluated by comparing the time to manually count the seeds to the time required to do the same task using the automated program. For 15 sets of images from 15 patients, the average time for manually counting the seeds was 45 minutes per patient versus 6.4 minutes on average per patients, the average time for manually counting the seeds was 45 minutes per patient versus 6.4 minutes on average per patient when the software was used to perform the same task. Using the interactive visualization and segmentation algorithm, the time required to count the seeds during post- implant dosimetry has been reduced by a factor of 7 compared to the existing manual technique.

  12. The tumor control probability model for transperineal permanent prostate brachytherapy and prostate-specific antigen failure free survival

    NASA Astrophysics Data System (ADS)

    Prete, James John

    1999-12-01

    The studies proposed were designed to investigate the relationship between transperineal permanent prostate implant quality, as modeled by the radiobiologicalquantifier of implant quality, tumor control probability (TCP), and treatment efficacy, as measured by prostatespecific antigen (PSA) failure free survival. It was hypothesized that TCP could be useful in identifying which patients, or group of patients, might be at an increased risk for treatment failure among patients receiving 125I transperineal permanent prostate brachytherapy (TPPB) as the sole modality of treatment for early or intermediate stage prostatic carcinoma. The formal statement of hypothesis was that the linear- quadratic tumor control probability model for monotherapeutic 125I transperineal permanent prostate brahytherapy correlates with prostate- specific antigen failure free survival. The specific aims were: [i]to implement the TCP model in a computerized treatment planning system for TPPB, using the recently recommended dose calculation formalism and benchmark data presented in AAPM TG43 and validate it, [ii]to compute and examine the relationship between TCP and PSA failure free survival for patients receiving monotherapeutic 125I TPPB, [iii]to investigate the influence of the definition of PSA failure on the relationship between TCP and PSA failure free survival rates, and [iv]to develop a method for improving the TCP model. The conclusions were: [i]the model as implemented using AAPM TG43 formalism, produced results which were similar to that calculated by the original model. TCP was demonstrated to correlate strongly and similarly with underdosed prostate volume in comparison to data published from the original model, [ii]an analysis of 125I implants demonstrated that patients stratified into the high TCP group had PSA failure free survival rates which were superior to the rates for patients in the low TCP group, regardless of which of the five definitions of PSA failure was applied to

  13. CsI(Na)-based radiation detector for high-resolution imaging studies using iodine 125 in small-animal research

    NASA Astrophysics Data System (ADS)

    Weisenberger, Andrew G.; Bradley, Eric; Majewski, Stan; Saha, Margaret

    1997-07-01

    We report on the development of a high resolution radiation imaging system which is capable of detecting and imaging the coincident gamma and x-ray emissions of the radioisotope iodine 125 ((superscript 125)I). Iodine 125 is commonly available as a label to molecular biology probes. Iodine 125 decays via electron capture emitting a 35 keV gamma-ray with the prompt emission of several 27 - 32 keV x rays. A coincidence condition can be set to detect the (superscript 125)I decays thus reducing background radiation contribution to the image. We are testing the use of arrays of CsI(Na) crystal scintillators coupled to position sensitive photomultiplier tubes for this application. Laboratory studies have thus far been done on mice using a prototype of our detector which is intended to be used to image gene expression in live mice to advance research in neurobiology.

  14. A comparative study of radical prostatectomy and permanent seed brachytherapy for low- and intermediate-risk prostate cancer

    PubMed Central

    Taussky, Daniel; Ouellet, Véronique; Delouya, Guila; Saad, Fred

    2016-01-01

    Introduction: We sought to compare the outcomes between radical prostatectomy (RP) and permanent seed prostate brachytherapy (PB) in patients with low- and low-intermediate-risk prostate cancer from a single tertiary care centre. Methods: Patients were selected from our institute’s internal database based on preoperative selection criteria from the National Comprehensive Cancer Network (NCCN) guidelines (2015) for low- and intermediate-risk patients. No patient had received any neo-adjuvant androgen-deprivation therapy. The endpoint was biochemical recurrence (BCR) or any salvage treatment for both RP and PB at 48 ± 4 months after treatment. The biochemical relapse threshold was set at prostate-specific antigen (PSA) ≥0.5 ng/mL for PB and two PSA values of ≥0.2 ng/mL for RP. Patients from both treatment groups were compared using non-parametric tests. A binary logistic regression analysis was performed to determine an association of treatment and pretreatment factors with a BCR at 48 months. Results: A total of 575 patients were included in this study; 254 were treated with RP and 321 with PB. BCR was not different between both groups (p=0.84, Chi-square test), and occurred in 21.2% of patients treated with RP and in 20.6% with PB. Based on univariate and multivariate logistic regression analyses, younger age, higher percentage of positive biopsies, and initial PSA were predictive of BCR. Treatment modality was not predictive in either univariate (odds ratio [OR] 0.96, 95% confidence interval [CI] 0.64–1.44; p=0.84) or multivariate (OR 1.43, 95% CI 0.89–2.30; p=0.14) analyses. Conclusions: Using closely related cutoff values for BCR, both RP and PB did not have significantly different outcomes at four years post-treatment. A longer followup may be necessary to detect a difference between treatments. PMID:27878044

  15. Greater Biopsy Core Number Is Associated With Improved Biochemical Control in Patients Treated With Permanent Prostate Brachytherapy

    SciTech Connect

    Bittner, Nathan; Wallner, Kent E.

    2010-11-15

    Purpose: Standard prostate biopsy schemes underestimate Gleason score in a significant percentage of cases. Extended biopsy improves diagnostic accuracy and provides more reliable prognostic information. In this study, we tested the hypothesis that greater biopsy core number should result in improved treatment outcome through better tailoring of therapy. Methods and Materials: From April 1995 to May 2006, 1,613 prostate cancer patients were treated with permanent brachytherapy. Patients were divided into five groups stratified by the number of prostate biopsy cores ({<=}6, 7-9, 10-12, 13-20, and >20 cores). Biochemical progression-free survival (bPFS), cause-specific survival (CSS), and overall survival (OS) were evaluated as a function of core number. Results: The median patient age was 66 years, and the median preimplant prostate-specific antigen was 6.5 ng/mL. The overall 10-year bPFS, CSS, and OS were 95.6%, 98.3%, and 78.6%, respectively. When bPFS was analyzed as a function of core number, the 10-year bPFS for patients with >20, 13-20, 10-12, 7-9 and {<=}6 cores was 100%, 100%, 98.3%, 95.8%, and 93.0% (p < 0.001), respectively. When evaluated by treatment era (1995-2000 vs. 2001-2006), the number of biopsy cores remained a statistically significant predictor of bPFS. On multivariate analysis, the number of biopsy cores was predictive of bPFS but did not predict for CSS or OS. Conclusion: Greater biopsy core number was associated with a statistically significant improvement in bPFS. Comprehensive regional sampling of the prostate may enhance diagnostic accuracy compared to a standard biopsy scheme, resulting in better tailoring of therapy.

  16. Iris melanoma management with iodine-125 plaque radiotherapy in 144 patients: impact of melanoma-related glaucoma on outcomes.

    PubMed

    Shields, Carol L; Shah, Sanket U; Bianciotto, Carlos G; Emrich, Jacqueline; Komarnicky, Lydia; Shields, Jerry A

    2013-01-01

    To evaluate the outcomes of iris melanoma managed with plaque radiotherapy on the basis of the initial presence or absence of glaucoma. Retrospective, comparative case series. A total of 144 patients. Custom-designed iodine-125 plaque radiotherapy delivering planned 8000 cGy to melanoma apex using transcorneal application. Tumor control and treatment-related complications. Of 144 patients with iris melanoma, glaucoma was present at the initial visit in 58 (40%). Causes of elevated intraocular pressure included angle infiltration by melanoma in 50 patients (86%), angle neovascularization in 4 patients (7%), and hyphema in 4 patients (7%). At presentation, the eyes displaying iris melanoma with glaucoma (vs. without glaucoma) were statistically more likely to display angle tumor (66% vs. 43%), with minimal thickness (1.9 vs. 2.9 mm), and melanoma seeding in iris stroma (7 vs. 3 clock hours) and angle (5 vs. 2 clock hours). Plaque radiotherapy was performed in all cases. Kaplan-Meier estimates at 7 years post-treatment revealed no statistical differences in outcomes of local recurrence (14% vs. 15%), enucleation (14% vs. 11%), or metastasis (2% vs. 0%) comparing eyes with and without glaucoma. Of the entire group, multivariate analysis for factors predictive of recurrence included partial (vs. complete) anterior segment irradiation and postradiotherapy glaucoma. Factors related to enucleation included diabetes mellitus, poor initial visual acuity, higher radiation dose to tumor apex, and tumor recurrence. There were no factors predictive of metastasis. Iodine-125 plaque radiotherapy provides adequate tumor control for iris melanoma with a low metastatic potential of 1% at 7 years. Iris melanoma with secondary glaucoma showed a statistically significant greater likelihood of flat tumor with iris and angle seeding and no difference in outcomes compared with eyes without glaucoma. The author(s) have no proprietary or commercial interest in any materials discussed in this

  17. Multi-Parametric MRI-Directed Focal Salvage Permanent Interstitial Brachytherapy for Locally Recurrent Adenocarcinoma of the Prostate: A Novel Approach

    PubMed Central

    Wallace, T.; Avital, I.; Stojadinovic, A.; Brücher, B.L.D.M.; Cote, E.; Yu, J.

    2013-01-01

    Even with the technological advances of dose-escalated IMRT with the addition of the latest image guidance technologies, local failures still occur. The combination of MRI-based imaging techniques can yield quantitative information that reflects on the biological properties of prostatic tissues. These techniques provide unique information that can be used for tumor detection in the treated gland. With the advent of these improved imaging modalities, it has become possible to more effectively image local recurrences within the prostate gland. With better imaging, these focal recurrences can be differentially targeted with salvage brachytherapy minimizing rectal and bladder toxicity. Here we report a novel use of MRI-directed focal brachytherapy after local recurrence. This technique offers a unique opportunity to safely and successfully treat recurrent prostate cancer, previously treated with definitive radiation therapy. The use of multi-parametric MRI-directed focal salvage permanent interstitial brachytherapy for locally recurrent adenocarcinoma of the prostate is a promising strategy to avoid more aggressive and expensive treatments that are associated with increased morbidity, potentially improving survival at potentially lower costs. PMID:23412660

  18. Multi-Parametric MRI-Directed Focal Salvage Permanent Interstitial Brachytherapy for Locally Recurrent Adenocarcinoma of the Prostate: A Novel Approach.

    PubMed

    Wallace, T; Avital, I; Stojadinovic, A; Brücher, B L D M; Cote, E; Yu, J

    2013-01-01

    Even with the technological advances of dose-escalated IMRT with the addition of the latest image guidance technologies, local failures still occur. The combination of MRI-based imaging techniques can yield quantitative information that reflects on the biological properties of prostatic tissues. These techniques provide unique information that can be used for tumor detection in the treated gland. With the advent of these improved imaging modalities, it has become possible to more effectively image local recurrences within the prostate gland. With better imaging, these focal recurrences can be differentially targeted with salvage brachytherapy minimizing rectal and bladder toxicity. Here we report a novel use of MRI-directed focal brachytherapy after local recurrence. This technique offers a unique opportunity to safely and successfully treat recurrent prostate cancer, previously treated with definitive radiation therapy. The use of multi-parametric MRI-directed focal salvage permanent interstitial brachytherapy for locally recurrent adenocarcinoma of the prostate is a promising strategy to avoid more aggressive and expensive treatments that are associated with increased morbidity, potentially improving survival at potentially lower costs.

  19. Use of brachytherapy in management of locally recurrent rectal cancer.

    PubMed

    Goes, R N; Beart, R W; Simons, A J; Gunderson, L L; Grado, G; Streeter, O

    1997-10-01

    Locally recurrent rectal cancer is associated with poor quality of life and has justified aggressive surgical and adjuvant approaches to control the disease. This study was designed to evaluate if the use of brachytherapy in association with wide surgical excision (debulking operation) can offer reasonable palliation for patients with locally recurrent rectal cancer. Patients with biopsy-proven locally recurrent rectal cancer who were not candidates for intraoperative radiation therapy and who were previously considered as having unresectable tumors were included in the study and were followed-up from May 1981 to November 1990. All of them had undergone laparotomy and had either radical or debulking surgical resection performed. At the same time, brachytherapy was used with temporary or permanent implant of seeds of iridium-192 or iodine-125. Thirty patients were included. Patients ranged in age from 28 to 74 years, and 16 patients were female. No mortality was observed, and morbidity was low (small-bowel obstruction (1 patient), intestinal fistula (1 patient), and urinary fistula (1 patient). Histologic examination of the specimen showed gross residual disease in 67 percent of patients and microscopic disease in 25 percent of patients. Long-term follow-up was possible in 28 patients. Mean follow-up and local control were, respectively, 26.5 months and 37.5 percent for gross residual disease and 34 months and 66 percent for microscopic residual disease. Eighteen patients (64 percent) had locally recurrent rectal cancer under control at the time of the last follow-up, with seven patients (25 percent) having no evidence of local or distant recurrence. This is the first report of brachytherapy for locally recurrent rectal cancer. This appears to offer a therapeutic alternative to patients who are not candidates for intraoperative radiation therapy. Surgical morbidity and mortality are acceptable. Local control in 18 patients (64 percent) is comparable with

  20. Photon counting readout pixel array in 0.18-μm CMOS technology for on-line gamma-ray imaging of 103palladium seeds for permanent breast seed implant (PBSI) brachytherapy

    NASA Astrophysics Data System (ADS)

    Goldan, A. H.; Karim, K. S.; Reznik, A.; Caldwell, C. B.; Rowlands, J. A.

    2008-03-01

    Permanent breast seed implant (PBSI) brachytherapy technique was recently introduced as an alternative to high dose rate (HDR) brachytherapy and involves the permanent implantation of radioactive 103Palladium seeds into the surgical cavity of the breast for cancer treatment. To enable accurate seed implantation, this research introduces a gamma camera based on a hybrid amorphous selenium detector and CMOS readout pixel architecture for real-time imaging of 103Palladium seeds during the PBSI procedure. A prototype chip was designed and fabricated in 0.18-μm n-well CMOS process. We present the experimental results obtained from this integrated photon counting readout pixel.

  1. [Outcomes and predictors of T3a prostate cancer treated by permanent interstitial brachytherapy combined with external radiotherapy and hormone therapy].

    PubMed

    Mai, Zhipeng; Yan, Weigang; Li, Hanzhong; Zhou, Yi; Zhou, Zhien; Chen, Jian

    2014-10-01

    To evaluate the outcomes of T3a prostate cancer treated by permanent interstitial brachytherapy combined with external radiotherapy and hormone therapy, and analyse the influence of preoperative factors on prognosis. From January 2003 to December 2008, 38 pactients with T3a prostate cancer aged from 48 to 81 years (mean: 71 years) were enrolled, with serum prostate specific antigen (PSA) levels ranged from 10.000 to 99.800 µg/L (mean: 56.300 µg/L), Gleason score from 5 to 9 (mean: 7.6) and percentage of positive biopsy cores from 10.0% to 100% (mean: 65.3%). All patients were treated by permanent interstitial brachytherapy combined with external radiotherapy and hormone therapy. Survival curves were calculated using the Kaplan-Meier method. The predictive factors including patient's age, prostate volume, serum pre-treatment PSA, Gleason score and percentage of positive biopsy cores were used for univariate analysis on biochemical failure-free, distant metastasis-free and overall survival. The mean follow-up was 69 months (range: 9-109 months).Nineteen patients experienced biochemical failure. The average biochemical failure time was 13.4 months (range: 1-40 months). There were 13 patients developed as distant metastatic prostate cancer since average 19.7 months (range: 1-70 months) after brachytherapy. Of all patients, 9 died of prostate cancer recurrence, while 6 passed away because of other reasons, with an average of 52.2 months (range: 9.0- 98.5 months). The 5-year biochemical failure-free survival (BFFS), distant metastasis free survival (DMFS), cancer specific survival (CSS) and overall survival (OS) rate were 44.1%, 68.6%, 82.4 and 75.8%, respectively. Twenty-nine patients experienced grade 1-2 gastrointestinal toxicity and 18 patients experienced grade 1-2 genitourinary toxicity. In univariate analysis, the percentage of positive biopsy cores was significantly correlated with BFFS (χ(2) = 17.240, P = 0.000), DMFS (χ(2) = 18.641, P = 0.000) and OS (χ(2

  2. Local Control Following Permanent Prostate Brachytherapy: Effect of High Biologically Effective Dose on Biopsy Results and Oncologic Outcomes

    SciTech Connect

    Stone, Nelson N.; Stock, Richard G.; Cesaretti, Jamie A.; Unger, Pam

    2010-02-01

    Purpose: To determine factors that influence local control and systemic relapse in patients undergoing permanent prostate brachytherapy (PPB). Methods and Materials: A total of 584 patients receiving PPB alone or PPB with external beam radiation therapy (19.5%) agreed to undergo prostate biopsy (PB) at 2 years postimplantion and yearly if results were positive or if the prostate-specific antigen (PSA) level increased. Short-term hormone therapy was used with 280 (47.9%) patients. Radiation doses were converted to biologically effective doses (BED) (using alpha/beta = 2). Comparisons were made by chi-square analysis and linear regression. Survival was determined by the Kaplan-Meier method. Results: The median PSA concentration was 7.1 ng/ml, and the median follow-up period was 7.1 years. PB results were positive for 48/584 (8.2%) patients. Positive biopsy results by BED group were as follows: 22/121 (18.2%) patients received a BED of <=150 Gy; 15/244 (6.1%) patients received >150 to 200 Gy; and 6/193 (3.1%; p < 0.001) patients received >200 Gy. Significant associations of positive PB results by risk group were low-risk group BED (p = 0.019), intermediate-risk group hormone therapy (p = 0.011) and BED (p = 0.040), and high-risk group BED (p = 0.004). Biochemical freedom from failure rate at 7 years was 82.7%. Biochemical freedom from failure rate by PB result was 84.7% for negative results vs. 59.2% for positive results (p < 0.001). Cox regression analysis revealed significant associations with BED (p = 0.038) and PB results (p = 0.002) in low-risk patients, with BED (p = 0.003) in intermediate-risk patients, and with Gleason score (p = 0.006), PSA level (p < 0.001), and PB result (p = 0.038) in high-risk patients. Fifty-three (9.1%) patients died, of which eight deaths were due to prostate cancer. Cause-specific survival was 99.2% for negative PB results vs. 87.6% for positive PB results (p < 0.001). Conclusions: Higher radiation doses are required to achieve local

  3. Local control following permanent prostate brachytherapy: effect of high biologically effective dose on biopsy results and oncologic outcomes.

    PubMed

    Stone, Nelson N; Stock, Richard G; Cesaretti, Jamie A; Unger, Pam

    2010-02-01

    To determine factors that influence local control and systemic relapse in patients undergoing permanent prostate brachytherapy (PPB). A total of 584 patients receiving PPB alone or PPB with external beam radiation therapy (19.5%) agreed to undergo prostate biopsy (PB) at 2 years postimplantion and yearly if results were positive or if the prostate-specific antigen (PSA) level increased. Short-term hormone therapy was used with 280 (47.9%) patients. Radiation doses were converted to biologically effective doses (BED) (using alpha/beta = 2). Comparisons were made by chi-square analysis and linear regression. Survival was determined by the Kaplan-Meier method. The median PSA concentration was 7.1 ng/ml, and the median follow-up period was 7.1 years. PB results were positive for 48/584 (8.2%) patients. Positive biopsy results by BED group were as follows: 22/121 (18.2%) patients received a BED of < or =150 Gy; 15/244 (6.1%) patients received >150 to 200 Gy; and 6/193 (3.1%; p < 0.001) patients received >200 Gy. Significant associations of positive PB results by risk group were low-risk group BED (p = 0.019), intermediate-risk group hormone therapy (p = 0.011) and BED (p = 0.040), and high-risk group BED (p = 0.004). Biochemical freedom from failure rate at 7 years was 82.7%. Biochemical freedom from failure rate by PB result was 84.7% for negative results vs. 59.2% for positive results (p < 0.001). Cox regression analysis revealed significant associations with BED (p = 0.038) and PB results (p = 0.002) in low-risk patients, with BED (p = 0.003) in intermediate-risk patients, and with Gleason score (p = 0.006), PSA level (p < 0.001), and PB result (p = 0.038) in high-risk patients. Fifty-three (9.1%) patients died, of which eight deaths were due to prostate cancer. Cause-specific survival was 99.2% for negative PB results vs. 87.6% for positive PB results (p < 0.001). Higher radiation doses are required to achieve local control following PPB. A BED of >200 Gy with an

  4. Relation of immediate and delayed thallium-201 distribution to localization of iodine-125 antimyosin antibody in acute experimental myocardial infarction

    SciTech Connect

    Khaw, B.A.; Strauss, H.W.; Pohost, G.M.; Fallon, J.T.; Katus, H.A.; Haber, E.

    1983-05-01

    Thallium-201 (TI-201) distribution in acute experimental myocardial infarction (MI) (n . 18) was compared with cardiac-specific antimyosin Fab (AM-Fab) uptake, a specific marker for myocardial necrosis. When antimyosin was injected 4 hours after ligation with TI-201 administered 23 hours 55 minutes later and measurement of myocardial distribution determined 5 minutes after intravenous administration of TI-201, (1) TI-201 distribution closely correlated with microsphere regional blood flow, and (2) an inverse exponential relation to iodine-125 (I-125) AM-Fab uptake was apparent. In another group of 4 animals, TI-201 and AM-Fab were administered intravenously 4 hours after MI, and 36 hours later myocardial distribution was measured. This delayed TI-201 distribution had a close inverse linear correlation with I-125 AM-Fab uptake. This inverse linear relation also was apparent in 28-hour-old MIs in dogs (n . 4) where collateral circulation had been established. TI-201 was administered intravenously at 27 hours after MI, and TI-201 distribution was determined 1 hour later. The present study demonstrated that whereas immediate TI-201 distribution is flow-limited, delayed TI-201 distribution is a marker of cell viability which, due to prolonged circulation time and redistribution, is not flow-limited.

  5. Implanting iodine-125 seeds into rat dorsal root ganglion for neuropathic pain: neuronal microdamage without impacting hind limb motion.

    PubMed

    Jiao, Ling; Zhang, Tengda; Wang, Huixing; Zhang, Wenyi; Fan, Saijun; Huo, Xiaodong; Zheng, Baosen; Ma, Wenting

    2014-06-15

    The use of iodine-125 ((125)I) in cancer treatment has been shown to relieve patients' pain. Considering dorsal root ganglia are critical for neural transmission between the peripheral and central nervous systems, we assumed that (125)I could be implanted into rat dorsal root ganglia to provide relief for neuropathic pain. (125)I seeds with different radioactivity (0, 14.8, 29.6 MBq) were implanted separately through L4-5 and L5-6 intervertebral foramen into the vicinity of the L5 dorsal root ganglion. von Frey hair results demonstrated the mechanical pain threshold was elevated after implanting (125)I seeds from the high radioactivity group. Transmission electron microscopy revealed that nuclear membrane shrinkage, nucleolar margination, widespread mitochondrial swelling, partial vacuolization, lysosome increase, and partial endoplasmic reticulum dilation were visible at 1,440 hours in the low radioactivity group and at 336 hours in the high radioactivity group. Abundant nuclear membrane shrinkage, partial fuzzy nuclear membrane and endoplasmic reticulum necrosis were observed at 1,440 hours in the high radioactivity group. No significant difference in combined behavioral scores was detected between preoperation and postoperation in the low and high radioactivity groups. These results suggested that the mechanical pain threshold was elevated after implanting (125)I seeds without influencing motor functions of the hind limb, although cell injury was present.

  6. High-Risk Prostate Cancer With Gleason Score 8-10 and PSA Level {<=}15 ng/ mL Treated With Permanent Interstitial Brachytherapy

    SciTech Connect

    Fang, L. Christine; Merrick, Gregory S.; Butler, Wayne M.; Galbreath, Robert W.; Murray, Brian C.; Reed, Joshua L.; Adamovich, Edward; Wallner, Kent E.

    2011-11-15

    Purpose: With widespread prostate-specific antigen (PSA) screening, there has been an increase in men diagnosed with high-risk prostate cancer defined by a Gleason score (GS) {>=}8 coupled with a relatively low PSA level. The optimal management of these patients has not been defined. Cause-specific survival (CSS), biochemical progression-free survival (bPFS), and overall survival (OS) were evaluated in brachytherapy patients with a GS {>=}8 and a PSA level {<=}15 ng/mL with or without androgen-deprivation therapy (ADT). Methods and Materials: From April 1995 to October 2005, 174 patients with GS {>=}8 and a PSA level {<=}15 ng/mL underwent permanent interstitial brachytherapy. Of the patients, 159 (91%) received supplemental external beam radiation, and 113 (64.9%) received ADT. The median follow-up was 6.6 years. The median postimplant Day 0 minimum percentage of the dose covering 90% of the target volume was 121.1% of prescription dose. Biochemical control was defined as a PSA level {<=}0.40 ng/mL after nadir. Multiple parameters were evaluated for impact on survival. Results: Ten-year outcomes for patients without and with ADT were 95.2% and 92.5%, respectively, for CSS (p = 0.562); 86.5% and 92.6%, respectively, for bPFS (p = 0.204); and 75.2% and 66.0%, respectively, for OS (p = 0.179). The median post-treatment PSA level for biochemically controlled patients was <0.02 ng/mL. Multivariate analysis failed to identify any predictors for CSS, whereas bPFS and OS were most closely related to patient age. Conclusions: Patients with GS {>=}8 and PSA level {<=}15 ng/mL have excellent bPFS and CSS after brachytherapy with supplemental external beam radiotherapy. The use of ADT did not significantly impact bPFS, CSS, or OS.

  7. Radio-guided occult lesion localisation using iodine 125 Seeds “ROLLIS” to guide surgical removal of an impalpable posterior chest wall melanoma metastasis

    SciTech Connect

    Dissanayake, Shashini; Dissanayake, Deepthi; Taylor, Donna B

    2015-09-15

    Cancer screening and surveillance programmes and the use of sophisticated imaging tools such as positron emission tomography-computed tomography (PET-CT) have increased the detection of impalpable lesions requiring imaging guidance for excision. A new technique involves intra-lesional insertion of a low-activity iodine-125 ({sup 125}I) seed and detection of the radioactive signal in theatre using a hand-held gamma probe to guide surgery. Whilst several studies describe using this method to guide the removal of impalpable breast lesions, only a handful of publications report its use to guide excision of lesions outside the breast. We describe a case in which radio-guided occult lesion localisation using an iodine 125 seed was used to guide excision of an impalpable posterior chest wall metastasis detected on PET-CT.

  8. Androgen-deprivation therapy does not impact cause-specific or overall survival after permanent prostate brachytherapy

    SciTech Connect

    Merrick, Gregory S. . E-mail: gmerrick@wheelinghospital.com; Butler, Wayne M.; Wallner, Kent E.; Galbreath, Robert W.; Allen, Zachariah A. M.S.; Adamovich, Edward

    2006-07-01

    Purpose: To determine if androgen-deprivation therapy (ADT) has an impact on cause-specific, biochemical progression-free, or overall survival after prostate brachytherapy. Methods and Materials: From April 1995 through June 2002, 938 consecutive patients underwent brachytherapy for clinical Stage T1b to T3a (2002 AJCC) prostate cancer. All patients underwent brachytherapy more than 3 years before analysis. A total of 382 patients (40.7%) received ADT with a duration of 6 months or less in 277 and more than 6 months in 105. The median follow-up was 5.4 years. Multiple clinical, treatment, and dosimetric parameters were evaluated as predictors of cause-specific, biochemical progression-free, and overall survival. Results: The 10-year cause-specific, biochemical progression-free, and overall survival rates for the entire cohort were 96.4%, 95.9%, and 78.1%, respectively. Except for biochemical progression-free survival in high-risk patients, ADT did not statistically impact any of the three survival categories. A Cox linear-regression analysis demonstrated that Gleason score was the best predictor of cause-specific survival, whereas percent-positive biopsies, prostate volume, and risk group predicted for biochemical progression-free survival. Patient age and tobacco use were the strongest predictors of overall survival. One hundred two patients have died, with 80 of the deaths a result of cardiovascular disease (54) and second malignancies (26). To date, only 12 patients have died of metastatic prostate cancer. Conclusions: After brachytherapy, androgen-deprivation therapy did not have an impact on cause-specific or overall survival for any risk group; however, ADT had a beneficial effect on biochemical progression-free survival in high-risk patients. Cardiovascular disease and second malignancies far outweighed prostate cancer as competing causes of death.

  9. Development of virtual patient models for permanent implant brachytherapy Monte Carlo dose calculations: interdependence of CT image artifact mitigation and tissue assignment

    NASA Astrophysics Data System (ADS)

    Miksys, N.; Xu, C.; Beaulieu, L.; Thomson, R. M.

    2015-08-01

    This work investigates and compares CT image metallic artifact reduction (MAR) methods and tissue assignment schemes (TAS) for the development of virtual patient models for permanent implant brachytherapy Monte Carlo (MC) dose calculations. Four MAR techniques are investigated to mitigate seed artifacts from post-implant CT images of a homogeneous phantom and eight prostate patients: a raw sinogram approach using the original CT scanner data and three methods (simple threshold replacement (STR), 3D median filter, and virtual sinogram) requiring only the reconstructed CT image. Virtual patient models are developed using six TAS ranging from the AAPM-ESTRO-ABG TG-186 basic approach of assigning uniform density tissues (resulting in a model not dependent on MAR) to more complex models assigning prostate, calcification, and mixtures of prostate and calcification using CT-derived densities. The EGSnrc user-code BrachyDose is employed to calculate dose distributions. All four MAR methods eliminate bright seed spot artifacts, and the image-based methods provide comparable mitigation of artifacts compared with the raw sinogram approach. However, each MAR technique has limitations: STR is unable to mitigate low CT number artifacts, the median filter blurs the image which challenges the preservation of tissue heterogeneities, and both sinogram approaches introduce new streaks. Large local dose differences are generally due to differences in voxel tissue-type rather than mass density. The largest differences in target dose metrics (D90, V100, V150), over 50% lower compared to the other models, are when uncorrected CT images are used with TAS that consider calcifications. Metrics found using models which include calcifications are generally a few percent lower than prostate-only models. Generally, metrics from any MAR method and any TAS which considers calcifications agree within 6%. Overall, the studied MAR methods and TAS show promise for further retrospective MC dose

  10. Evaluation of the dosimetric parameters for 125I brachytherapy determined in prostate medium using CT images.

    PubMed

    Hanada, Takashi; Yorozu, Atsunori; Ohashi, Toshio; Shigematsu, Naoyuki; Maruyama, Koichi

    2010-01-01

    In the present study, the prostate medium determined from the CT images of 149 patients was developed. The dosimetric parameters such as Λ, g(L)(r) and F(r, θ) used in TG-43U1-based calculation for an iodine-125 ((125)I) brachytherapy-source were examined using Monte Carlo code Geant4. Clinical dosimetry parameters such as the D(90) were evaluated among a subgroup of 50 randomly selected patients who had been treated with permanent brachytherapy between January 2008 and December 2008 at the Tokyo Medical Center. The results show a slight difference in the dose rate constant Λ (within 1.0%). The radial dose function g(L)(r) exhibits a prominent difference in the region over 3 cm, and this difference is maintained within 2.9% in the region close to the source. The calculated values of F(r, θ) for the prostate medium were similar to values for water (within 1%), except in the longitudinal axis. A comparison of D(90) values shows a systematic dose overestimation of 2.8 ± 0.7 Gy in water, where the distribution of the differences can be seen with a spread of 1.8 ± 0.3% compared to that in prostate medium. It was concluded that the introduction of any kind of tissue correction for the TG-43U1-based calculation was not necessary to allow for the differences in elemental compositions and densities between water and prostate medium. PACS number: 87.00.00; 87.55.dk; 87.55.K-; 87.56.B-.

  11. In vivo imaging of insulin receptors by PET: preclinical evaluation of iodine-125 and iodine-124 labelled human insulin.

    PubMed

    Iozzo, P; Osman, S; Glaser, M; Knickmeier, M; Ferrannini, E; Pike, V W; Camici, P G; Law, M P

    2002-01-01

    [A(14)-*I]iodoinsulin was prepared for studies to assess the suitability of labeled iodoinsulin for positron emission tomography (PET). Iodine-125 was used to establish the methods and for preliminary studies in rats. Further studies and PET scanning in rats were carried out using iodine-124. Tissue and plasma radioactivity was measured as the uptake index (UI = [cpm x (g tissue)(-1)]/[cpm injected x (g body weight)(-1)]) at 1 to 40 min after intravenous injection of either [A(14)-(125)I]iodoinsulin or [A(14)-(124)I]iodoinsulin. For both radiotracers, initial clearance of radioactivity from plasma was rapid (T(1/2) approximately 1 min), reaching a plateau (UI = 2.8) at approximately 5 min which was maintained for 35 min. Tissue biodistributions of the two radiotracers were comparable; at 10 min after injection, UI for myocardium was 2.4, liver, 4.0, pancreas, 5.4, brain, 0.17, kidney, 22, lung, 2.3, muscle, 0.54 and fat, 0.28. Predosing rats with unlabelled insulin reduced the UI for myocardium (0.95), liver (1.8), pancreas (1.2) and brain (0.08), increased that for kidney (61) but had no effect on that for lung (2.5), muscle (0.50) or fat (0.34). Analysis of radioactivity in plasma demonstrated a decrease of [(125)I]iodoinsulin associated with the appearance of labeled metabolites; the percentage of plasma radioactivity due to [(125)I]iodoinsulin was 40% at 5 min and 10% at 10 min. The heart, liver and kidneys were visualized using [(124)I]iodoinsulin with PET.

  12. Simultaneous technetium-99 MAG(3), iodine-131-orthoiodohippurate and iodine-125 iothalamate clearance and biodistribution after bolus injection in rats.

    PubMed

    Casadevall, G; Turull, A; Piera, C; Queralt, J

    2000-07-01

    A bolus injection multiple blood sampling method was developed for the simultaneous measurement of blood and plasma clearance of three radiopharmaceuticals in rats. Technetium-99m mercaptoacetyltriglycine ([(99m)Tc]MAG(3)) and iodine-131-orthoiodohippurate ([(131)I]OIH) were used as makers of effective renal blood flow (ERBF), and iodine-125 iothalamate ([(125)I]IOT) was used as a marker of glomerular filtration rate (GFR). These methods can be easily performed in rats without arterial catheterization. Tissue biodistribution was studied in four groups of rats subjected to the following: group A, renal pedicle isolation (sham-operated); group B, ligature of one kidney pedicle; group C, ligature of both renal pedicles; and group D, ligature of both kidney pedicles and the bile duct. Renal clearance of [(99m)Tc]MAG(3) was greater than [(131)I]OIH and both agents were cleared faster than ([(125)I]-IOT). Either of the two markers of ERBF may be used in experimental studies, but it should be borne in mind that these are relative measurements of kidney performance. [(99m)Tc]MAG(3) and [(125)I]-IOT showed bile excretion in healthy rats, so they cannot completely fulfill the requirements for use as markers of ERBF. When renal function was impaired experimentally, [(99m)Tc]MAG(3) and [(125)I]-IOT were excreted in bile and [(131)I]OIH was secreted in the intestine. Thus, while the markers of ERBF and GFR may be reliable under normal physiological conditions, they may give progressively more erroneous values as renal function deteriorates.

  13. Uveal Melanoma Treated with Iodine-125 Episcleral Plaque: An Analysis of Dose on Disease Control and Visual Outcomes

    PubMed Central

    Perez, Bradford A.; Mettu, Pradeep; Vajzovic, Lejla; Rivera, Douglas; Alkaissi, Ali; Steffey, Beverly A.; Cai, Jing; Stinnett, Sandra; Dutton, Jonathan J.; Buckley, Edward G.; Halperin, Edward; Marks, Lawrence B.; Mruthyunjaya, Prithvi; Kirsch, David G.

    2014-01-01

    PURPOSE In the treatment of uveal melanomas, the optimal prescribed dose to maximize disease control, but minimize radiation-related complications is unknown. Historically our institution has treated uveal melanomas to doses less than 85 Gy to the tumor apex even if the apex was less than 5mm in height. Here, we investigate how tumor control and visual outcomes are affected by the radiation dose at the tumor apex. METHODS AND MATERIALS A retrospective review was performed to evaluate patients treated for uveal melanoma with Iodine-125 plaques between 1988 and 2010. Radiation dose is reported as dose to tumor apex and dose to 5 mm. Primary end points included time to local failure, distant failure, and death. Secondary end points included eye preservation, visual acuity, and radiation-related complications. Univariate and multivariate analyses were performed to determine association between radiation dose and the end point variables. RESULTS One hundred ninety patients with sufficient data to evaluate the end points were included. The 5 year local control (LC) rate was 91%. The 5 year distant metastases (DM) rate was 10%. The 5 year overall survival (OS) rate was 84%. There were no differences in outcome (LC, DM, OS) when dose was stratified by apex dose quartile (<69 Gy, 69–81 Gy, 81–89 Gy, >89 Gy). However, increasing apex dose and dose to 5 mm depth were correlated with greater visual acuity loss (p=0.02, p=0.0006), worse final visual acuity (p=0.02, p<0.0001) and radiation complications (p<0.0001, p=0.0009). In addition, enucleation rates were worse with increasing quartiles of dose to 5 mm (p=0.0001). CONCLUSIONS Doses at least as low as 69 Gy prescribed to the tumor apex achieve rates of local control, distant metastasis free survival, and overall survival that are similar to radiation doses of 85 Gy to the tumor apex, but with improved visual outcomes. PMID:24613808

  14. Survival following interstitial brachytherapy for recurrent malignant glioma.

    PubMed

    Kitchen, N D; Hughes, S W; Taub, N A; Sofat, A; Beaney, R P; Thomas, D G

    1994-01-01

    The treatment of recurrent malignant glioma is difficult and at present largely disappointing. Furthermore the results of any treatment modality need to be interpreted with knowledge regarding patient selection and timing of treatment. The results of interstitial brachytherapy using iodine-125 in 23 patients are presented. There were no operative complications. Median survival time from tumour recurrence and implantation was 36 and 25 weeks respectively. Karnofsky Performance Status (KPS) was significantly associated with survival, though patient age, original tumour histology, prior chemotherapy, and time to recurrence were not. Treatment does confer modest survival benefit as compared to controls, but our results are not as impressive as others. Reasons for this finding are discussed.

  15. Canadian prostate brachytherapy in 2012

    PubMed Central

    Keyes, Mira; Crook, Juanita; Morris, W. James; Morton, Gerard; Pickles, Tom; Usmani, Nawaid; Vigneault, Eric

    2013-01-01

    Prostate brachytherapy can be used as a monotherapy for low- and intermediate-risk patients or in combination with external beam radiation therapy (EBRT) as a form of dose escalation for selected intermediate- and high-risk patients. Prostate brachytherapy with either permanent implants (low dose rate [LDR]) or temporary implants (high dose rate [HDR]) is emerging as the most effective radiation treatment for prostate cancer. Several large Canadian brachytherapy programs were established in the mid- to late-1990s. Prostate brachytherapy is offered in British Columbia, Alberta, Manitoba, Ontario, Quebec and New Brunswick. We anticipate the need for brachytherapy services in Canada will significantly increase in the near future. In this review, we summarize brachytherapy programs across Canada, contemporary eligibility criteria for the procedure, toxicity and prostate-specific antigen recurrence free survival (PRFS), as published from Canadian institutions for both LDR and HDR brachytherapy. PMID:23671495

  16. Towards clinical application of RayStretch for heterogeneity corrections in LDR permanent (125)I prostate brachytherapy.

    PubMed

    Hueso-González, Fernando; Ballester, Facundo; Perez-Calatayud, Jose; Siebert, Frank-André; Vijande, Javier

    RayStretch is a simple algorithm proposed for heterogeneity corrections in low-dose-rate brachytherapy. It is built on top of TG-43 consensus data, and it has been validated with Monte Carlo (MC) simulations. In this study, we take a real clinical prostate implant with 71 (125)I seeds as reference and we apply RayStretch to analyze its performance in worst-case scenarios. To do so, we design two cases where large calcifications are located in the prostate lobules. RayStretch resilience under various calcification density values is also explored. Comparisons against MC calculations are performed. Dose-volume histogram-related parameters like prostate D90, rectum D2cc, or urethra D10 obtained with RayStretch agree within a few percent with the detailed MC results for all cases considered. The robustness and compatibility of RayStretch with commercial treatment planning systems indicate its applicability in clinical practice for dosimetric corrections in prostate calcifications. Its use during intraoperative ultrasound planning is foreseen. Copyright © 2017 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  17. Early biochemical outcomes following permanent interstitial brachytherapy as monotherapy in 1050 patients with clinical T1-T2 prostate cancer.

    PubMed

    Guedea, Ferran; Aguilo, Ferran; Polo, Alfredo; Langley, Stephen; Laing, Robert; Henderson, Alastair; Aaltomaa, Sirpa; Kataja, Vesa; Palmgren, Juni; Bladou, Franch; Salem, Naji; Gravis, Gwenaelle; Losa, Andrea; Guazzoni, Giorgio; Nava, Luciano

    2006-07-01

    Five European centres (France, Finland, Italy, Spain and the UK) have pooled data to generate a large patient series involving 1175 patients treated with prostate brachytherapy. This paper reports preliminary data on PSA outcome up to 4 years. Out of 1175 in the database, 1050 patients with localised prostate cancer who had received transperineal seed implantation as monotherapy between May 1998 and August 2003 were stage T1-T2. A total of 668 (63.6%) patients met the low-risk group definition, 297 (28.3%) as intermediate-risk definition and 66 (6.3%) the high-risk group definition. The majority of patients were Gleason score 6 or less (n=951) and disease stage was T1c in 557 patients. Of the 1050 patients, PSA data up to 4 years were available for 210 patients, while 364 patients with PSA values up to 36 months were evaluable by the Kaplan-Meier method for freedom from biochemical failure. The biochemical progression-free rate at 3 years was estimated to be 91%, with a 93% and 88% rate for low- and intermediate-risk groups, respectively, versus 80% for the high-risk group. PSA kinetics provide encouraging evidence of treatment efficacy. These data on 4-year PSA follow-up on patients treated with prostate brachytherapy reflect those previously reported in the literature. This patient series will be followed to provide long-term outcome in the future.

  18. Evaluation of the visibility of a new thinner ¹²⁵I radioactive source for permanent prostate brachytherapy.

    PubMed

    Roberts, Gemma; Al-Qaisieh, Bashar; Bownes, Peter

    2012-01-01

    The ¹²⁵I source currently used for prostate brachytherapy at St. James's Institute of Oncology is a standard size seed (≈4.5mm in length and 0.8mm in diameter). A new, thinner seed is under evaluation. This is designed to be implanted using narrower needles, potentially reducing edema and improving the dose distribution. This study investigated the visibility of the thinner source on multimodality images and compared it with that of standard size seeds. Images of dummy seeds of both thinner and standard size models were taken using ultrasound, fluoroscopy, computed tomography (CT), and magnetic resonance (MR) imaging. The ultrasound, fluoroscopy, and CT images were acquired with the seeds inserted into phantoms positioned in a water tank. The MR images were acquired using phantoms containing single seeds. The images were analyzed visually and quantitatively. The resolution of closely spaced seeds on CT images was investigated. The visibility of both seeds was similar on ultrasound, fluoroscopy, and MR images. On CT images, the thinner seeds give reduced artifacts and better resolution. The use of the thinner seed would have minimal effect on ultrasound and fluoroscopy imaging during treatment. However on CT images, the use of the thinner seeds may improve seed identification for post-treatment dosimetry. Further study is required into the suitability of MR images alone for post-treatment dosimetry. Copyright © 2012 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  19. Randomized non-inferiority trial of Bicalutamide and Dutasteride versus LHRH agonists for prostate volume reduction prior to I-125 permanent implant brachytherapy for prostate cancer.

    PubMed

    Gaudet, Marc; Vigneault, Éric; Foster, William; Meyer, François; Martin, André-Guy

    2016-01-01

    To determine the efficacy and toxicity of a 3-month regimen of Dutasteride and Bicalutamide compared to LHRH agonists for prostate volume (PV) reduction prior to permanent implant prostate brachytherapy (PIPB). Patients with low-risk or low-tier intermediate risk prostate cancer eligible for PIPB with a prostate volume greater than 50 cc were randomized to either Dutasteride 0.5 mg Bicalutamide 50 mg daily and Tamoxifen 10 mg daily for 3 months (D+B group) or to a 3 month dose of an LHRH agonist and Bicalutamide daily for 1 month (LHRH group). Their PV was measured at baseline and at pre-implant. Non-inferiority analysis was completed for the relative (%) PV reduction. IPSS and EPIC questionnaires were completed at baseline, pre-implant and at 1, 3, 6, 12, 18 and 24 months post-treatment. IPSS and EPIC comparisons were based on superiority analysis 60 patients were randomized (31 to LHRH group and 29 to D+B group). Mean relative PV reduction (SD) was 35.5% (8.9) in the LHRH group and 31.7% (9.6) in the D+B group. The upper bound of the 95% confidence for the interval for the difference between groups favouring LHRH agonists for PV reduction was 8.6 which did not cross the 10% non-inferiority margin meaning D+B is non-inferior to LHRH agonist for PV reduction, although 5/29 (17%) of those in the D+B group required longer duration of D+B to achieve adequate volume reduction. There were no statistically significant differences in IPSS scores over the entire follow-up period. EPIC sexual summary score was significantly better in the D+B group at pre-implant, 1 month, 3 months post-implant. Dutasteride and Bicalutamide is a regimen of non-inferior efficacy to LHRH agonist based regimens for prostate volume reduction prior to permanent implant prostate brachytherapy. D+B has less sexual toxicity compared to LHRH agonists prior to implant and for the first 6 months after implant. D+B is therefore an option to be considered for prostate volume reduction prior to PIPB

  20. The American College of Radiology and the American Brachytherapy Society practice parameter for the performance of low-dose-rate brachytherapy.

    PubMed

    Viswanathan, Akila N; Erickson, Beth A; Ibbott, Geoffrey S; Small, William; Eifel, Patricia J

    Brachytherapy is the use of radionuclides to treat malignancies or benign conditions by means of a radiation source placed close to or into the tumor or treatment site. This practice parameter refers only to the use of radionuclide brachytherapy. Brachytherapy alone or combined with external beam therapy plays an important role in the management and treatment of patients with cancer. Low-dose-rate (LDR) brachytherapy has traditionally been used for treating prostate, head and neck, breast, cervical, and endometrial cancers as well as obstructive bile duct, esophageal, or bronchial lesions. It has been practiced for over a century with a variety of sources including radium-226, cesium-137, and, more recently, iridium- 192, iodine-125, and palladium-103. Low-dose-rate (LDR) brachytherapy can be given as interstitial, intracavitary, intraluminal, and/or plesiotherapy to a wide variety of treatment sites. This practice parameter addresses sealed sources as they are used for LDR brachytherapy. It is recognized that unsealed sources (e.g., yttrium-90) are also a form of LDR brachytherapy. Copyright © 2016 American Brachytherapy Society and American College of Radiology. Published by Elsevier Inc. All rights reserved.

  1. Treatment planning for brachytherapy: an integer programming model, two computational approaches and experiments with permanent prostate implant planning.

    PubMed

    Lee, E K; Gallagher, R J; Silvern, D; Wuu, C S; Zaider, M

    1999-01-01

    An integer linear programming model is proposed as a framework for optimizing seed placement and dose distribution in brachytherapy treatment planning. The basic model involves using 0/1 indicator variables to describe the placement or non-placement of seeds in a prespecified three-dimensional grid of potential locations. The dose delivered to each point in a discretized representation of the diseased organ and neighbouring healthy tissue can then be modelled as a linear combination of the indicator variables. A system of linear constraints is imposed to attempt to keep the dose level at each point to within specified target bounds. Since it is physically impossible to satisfy all constraints simultaneously, each constraint uses a variable to either record when the target dose level is achieved, or to record the deviation from the desired level. These additional variables are embedded into an objective function to be optimized. Variations on this model are discussed and two computational approaches--a branch-and-bound algorithm and a genetic algorithm--for finding 'optimal' seed placements are described. Results of computational experiments on a collection of prostate cancer cases are reported. The results indicate that both optimization algorithms are capable of producing good solutions within 5 to 15 min, and that small variations in model parameters can have a measurable effect on the dose distribution of the resulting plans.

  2. A radiobiology-based inverse treatment planning method for optimisation of permanent l-125 prostate implants in focal brachytherapy

    NASA Astrophysics Data System (ADS)

    Haworth, Annette; Mears, Christopher; Betts, John M.; Reynolds, Hayley M.; Tack, Guido; Leo, Kevin; Williams, Scott; Ebert, Martin A.

    2016-01-01

    Treatment plans for ten patients, initially treated with a conventional approach to low dose-rate brachytherapy (LDR, 145 Gy to entire prostate), were compared with plans for the same patients created with an inverse-optimisation planning process utilising a biologically-based objective. The ‘biological optimisation’ considered a non-uniform distribution of tumour cell density through the prostate based on known and expected locations of the tumour. Using dose planning-objectives derived from our previous biological-model validation study, the volume of the urethra receiving 125% of the conventional prescription (145 Gy) was reduced from a median value of 64% to less than 8% whilst maintaining high values of TCP. On average, the number of planned seeds was reduced from 85 to less than 75. The robustness of plans to random seed displacements needs to be carefully considered when using contemporary seed placement techniques. We conclude that an inverse planning approach to LDR treatments, based on a biological objective, has the potential to maintain high rates of tumour control whilst minimising dose to healthy tissue. In future, the radiobiological model will be informed using multi-parametric MRI to provide a personalised medicine approach.

  3. A prospective longitudinal study comparing a radical retropubic prostatectomy and permanent prostate brachytherapy regarding the health-related quality of life for localized prostate cancer.

    PubMed

    Hashine, Katsuyoshi; Kusuhara, Yoshito; Miura, Noriyoshi; Shirato, Akitomi; Sumiyoshi, Yoshiteru; Kataoka, Masaaki

    2008-07-01

    The health-related quality of life (HRQOL) after a radical retropubic prostatectomy (RRP) or a permanent prostate brachytherapy (PPB) was prospectively compared at a single institute. Between 2003 and 2005, 122 patients were treated by RRP and 82 patients were treated by PPB. A QOL survey was completed at baseline, and 1, 3, 6 and 12 months after treatment, prospectively. The general HRQOL was not different between the RRP and PPB groups after 3 months. However, at 1 month after treatment, the general HRQOL scores, except for general health, were significantly better in the PPB group than that in the RRP group. Moreover, the disease-specific QOL was worse in urinary and sexual functions in the RRP group. Urinary function in the RRP group had not recovered to baseline after 12 months. Although the urinary function in the PPB group was better than that of the RRP group, urinary bother continued to worsen until 6 months and thereafter it recovered gradually. The bowel function was not worse in the PPB group but bowel bother was worse at 6 months in the PPB group. In the RRP group, the patients with nerve sparing demonstrated better in sexual function than those without nerve sparing, but the recovery did not reach the level of the PPB group. This prospective study revealed the differences in the QOL after RRP and PPB. These results will be helpful for making treatment decisions.

  4. Health-related quality of life using SF-8 and EPIC questionnaires after treatment with radical retropubic prostatectomy and permanent prostate brachytherapy.

    PubMed

    Hashine, Katsuyoshi; Kusuhara, Yoshito; Miura, Noriyoshi; Shirato, Akitomi; Sumiyoshi, Yoshiteru; Kataoka, Masaaki

    2009-08-01

    The health-related quality of life (HRQOL) after treatment of prostate cancer is examined using a new HRQOL tool. HRQOL, based on the expanded prostate cancer index composite (EPIC) and SF-8 questionnaires, was prospectively compared after either a radical retropubic prostatectomy (RRP) or a permanent prostate brachytherapy (PPB) at a single institute. Between October 2005 and June 2007, 96 patients were treated by an RRP and 88 patients were treated by a PPB. A HRQOL survey was completed at baseline, and at 1, 3, 6 and 12 months after treatment, prospectively. The general HRQOL in the RRP and PPB groups was not different after 3 months. However, at baseline and 1 month after treatment, the mental component summary was significantly better in the PPB group than in the RRP group. Moreover, the disease-specific HRQOL was worse regarding urinary and sexual functions in the RRP group. Urinary irritative/obstructive was worse in the PPB group, but urinary incontinence was worse in the RRP group and had not recovered to baseline after 12 months. The bowel function and bother were worse in the PPB group than in the RRP group after 3 months. In the RRP group, the patients with nerve sparing demonstrated the same scores in sexual function as the PPB group. This prospective study revealed the differences in the HRQOL after an RRP and PPB. Disease-specific HRQOL is clarified by using EPIC survey. These results will be helpful for making treatment decisions.

  5. Comparison of biochemical failure rates between permanent prostate brachytherapy and radical retropubic prostatectomy as a function of posttherapy PSA nadir plus 'X'.

    PubMed

    Ahmed, Kamran A; Davis, Brian J; Mynderse, Lance A; Slezak, Jeffrey M; Bergstralh, Eric J; Wilson, Torrence M; Choo, C Richard

    2014-07-29

    Prostate-specific antigen (PSA) nadir + 2 ng/mL, also known as the Phoenix definition, is the definition most commonly used to establish biochemical failure (BF) after external beam radiotherapy for prostate cancer management. The purpose of this study is to compare BF rates between permanent prostate brachytherapy (PPB) and radical retropubic prostatectomy (RRP) as a function of PSA nadir plus varying values of X and examine the associated implications. We retrospectively searched for patients who underwent PPB or RRP at our institution between 1998 and 2004. Only primary patients not receiving androgen-deprivation therapy were included in the study. Three RRP patients were matched to each PPB patient on the basis of prognostic factors. BF rates were estimated for PSA nadirs + different values of X. A total of 1,164 patients were used for analysis: 873 in the RRP group and 291 in the PPB group. Patients were equally matched by clinical stage, biopsy Gleason sum, primary Gleason grade, and pretherapy PSA value. Median follow-up was 3.1 years for RRP patients and 3.6 years in the PPB group (P = .01). Using PSA nadir + 0.1 ng/mL for the definition of BF, the 5-year BF rate was 16.3% for PPB patients and 13.5% for RRP patients (P = .007), whereas at nadir + 2 ng/mL or greater, the BF rates were less than 3% and were indistinguishable between PPB and RRP patients. In a cohort of well-matched patients who had prostatectomy or brachytherapy, we examined BF as a function of nadir + X, where X was treated as a continuous variable. As X increases from 0.1 to 2.0 ng/mL, the BF curves converge, and above 2.0 ng/mL they are essentially indistinguishable. The data presented are of interest as BF definitions continue to evolve.

  6. Feasibility of vibro-acoustography with a quasi-2D ultrasound array transducer for detection and localizing of permanent prostate brachytherapy seeds: A pilot ex vivo study

    SciTech Connect

    Mehrmohammadi, Mohammad; Kinnick, Randall R.; Fatemi, Mostafa; Alizad, Azra; Davis, Brian J.

    2014-09-15

    Purpose: Effective permanent prostate brachytherapy (PPB) requires precise placement of radioactive seeds in and around the prostate. The impetus for this research is to examine a new ultrasound-based imaging modality, vibro-acoustography (VA), which may serve to provide a high rate of PPB seed detection while also effecting enhanced prostate imaging. The authors investigate the ability of VA, implemented on a clinical ultrasound (US) scanner and equipped with a quasi-2D (Q2D) array US transducer, to detect and localize PPB seeds in excised prostate specimens. Methods: Nonradioactive brachytherapy seeds were implanted into four excised cadaver prostates. A clinical US scanner equipped with a Q2D array US transducer was customized to acquire both US and C-scan VA images at various depths. The VA images were then used to detect and localize the implanted seeds in prostate tissue. To validate the VA results, computed tomography (CT) images of the same tissue samples were obtained to serve as the reference by which to evaluate the performance of VA in PPB seed detection. Results: The results indicate that VA is capable of accurately identifying the presence and distribution of PPB seeds with a high imaging contrast. Moreover, a large ratio of the PPB seeds implanted into prostate tissue samples could be detected through acquired VA images. Using CT-based seed identification as the standard, VA was capable of detecting 74%–92% of the implanted seeds. Additionally, the angular independency of VA in detecting PPB seeds was demonstrated through a well-controlled phantom experiment. Conclusions: Q2DVA detected a substantial portion of the seeds by using a 2D array US transducer in excised prostate tissue specimens. While VA has inherent advantages associated with conventional US imaging, it has the additional advantage of permitting detection of PPB seeds independent of their orientation. These results suggest the potential of VA as a method for PPB imaging that

  7. Feasibility of vibro-acoustography with a quasi-2D ultrasound array transducer for detection and localizing of permanent prostate brachytherapy seeds: A pilot ex vivo study

    PubMed Central

    Mehrmohammadi, Mohammad; Alizad, Azra; Kinnick, Randall R.; Davis, Brian J.; Fatemi, Mostafa

    2014-01-01

    Purpose: Effective permanent prostate brachytherapy (PPB) requires precise placement of radioactive seeds in and around the prostate. The impetus for this research is to examine a new ultrasound-based imaging modality, vibro-acoustography (VA), which may serve to provide a high rate of PPB seed detection while also effecting enhanced prostate imaging. The authors investigate the ability of VA, implemented on a clinical ultrasound (US) scanner and equipped with a quasi-2D (Q2D) array US transducer, to detect and localize PPB seeds in excised prostate specimens. Methods: Nonradioactive brachytherapy seeds were implanted into four excised cadaver prostates. A clinical US scanner equipped with a Q2D array US transducer was customized to acquire both US and C-scan VA images at various depths. The VA images were then used to detect and localize the implanted seeds in prostate tissue. To validate the VA results, computed tomography (CT) images of the same tissue samples were obtained to serve as the reference by which to evaluate the performance of VA in PPB seed detection. Results: The results indicate that VA is capable of accurately identifying the presence and distribution of PPB seeds with a high imaging contrast. Moreover, a large ratio of the PPB seeds implanted into prostate tissue samples could be detected through acquired VA images. Using CT-based seed identification as the standard, VA was capable of detecting 74%–92% of the implanted seeds. Additionally, the angular independency of VA in detecting PPB seeds was demonstrated through a well-controlled phantom experiment. Conclusions: Q2DVA detected a substantial portion of the seeds by using a 2D array US transducer in excised prostate tissue specimens. While VA has inherent advantages associated with conventional US imaging, it has the additional advantage of permitting detection of PPB seeds independent of their orientation. These results suggest the potential of VA as a method for PPB imaging that

  8. [Physical and technical quality assurance and radiation protection in transperineal interstitial permanent prostate brachytherapy with 125-iodine seeds].

    PubMed

    Kaulich, Theodor W; Lamprecht, Ulf; Paulsen, Frank; Lorenz, Joachim; Maurer, Uwe; Loeser, Wolfgang; Bichler, Karl-Horst; Nüsslin, Fridtjof; Bamberg, Michael

    2002-12-01

    Early stage prostate cancer can be treated successfully by interstitial brachytherapy with 125-iodine seeds. A quality-assurance programme is presented that was designed for this purpose for internal clinical use. Furthermore the requirements of the new German Ordinance Governing Radiation Protection (StrlSchV) that came into force on August 1, 2001, are taken into account. For the 125-iodine monotherapy of the prostate we used RAPID STRANDS (Amersham Health, Braunschweig, Germany). According to the guidelines of the new Ordinance Governing Radiation Protection, the determination of the body dose of the staff is made to rely on the new measurement quantities H(p) (10) and H(p) (0.07). The nominal air kerma rate of the seeds is measured with a calibrated well-chamber of the type HDR 1000 Plus and an electrometer of the type MAX 4000 (Standard Imaging Inc., USA). The ultrasound images of the prostate are produced by an ultrasound device of the type Falcon 2101 (B-K Medical, Denmark). For treatment planning the programme VariSeed (Varian, Darmstadt, Germany) was employed. Correct loading of the needles is controlled by autoradiography before implantation. After the implantation radiation-protection measurements in the operating room are carried out. As regards the personnel, for the depth personal dose equivalent Hp(10) and relating to two applications each, measurement values between 0 microSv and 14 microSv resulted. The control of the radiation exposure of the hands revealed superficial personal dose values H(p) (0.07) of up to 1 mSv. The nominal air kerma rates of the RAPID STRANDS were all lying within the 95% confidence interval guaranteed by the producer. The autoradiographs documented -- except for one case -- the correct loading of the needles. The interstitial transperineal prostate implantation of the 125-iodine seeds succeeded as planned with all patients. Until now no contamination of the operating room was detected by the radiation

  9. A detailed radiobiological and dosimetric analysis of biochemical outcomes in a case-control study of permanent prostate brachytherapy patients.

    PubMed

    Butler, Wayne M; Stewart, Renee R; Merrick, Gregory S

    2009-03-01

    generalized EUD. In this case-control study of prostate brachytherapy biochemical failures and nonfailures, there were no radiobiological parameters derived from detailed DVH-based analysis that predicted for biochemical control. This may indicate that in our approach, implant dosimetry is at or near the limits of clinically effective dose escalation.

  10. A detailed radiobiological and dosimetric analysis of biochemical outcomes in a case-control study of permanent prostate brachytherapy patients

    SciTech Connect

    Butler, Wayne M.; Stewart, Renee R.; Merrick, Gregory S.

    2009-03-15

    the harmonic mean and expressions of the generalized EUD. In this case-control study of prostate brachytherapy biochemical failures and nonfailures, there were no radiobiological parameters derived from detailed DVH-based analysis that predicted for biochemical control. This may indicate that in our approach, implant dosimetry is at or near the limits of clinically effective dose escalation.

  11. Stereotactic brachytherapy of low-grade cerebral glioma after tumor resection.

    PubMed

    Suchorska, Bogdana; Ruge, Maximilian; Treuer, Harald; Sturm, Volker; Voges, Jürgen

    2011-10-01

    The purpose of this study was to assess the impact of stereotactic brachytherapy (SBT) on survival time and outcome when applied after resection of low-grade glioma (LGG) of World Health Organization grade II. From January 1982 through December 2006 we treated 1024 patients who had glioma with stereotactic implantation of iodine-125 seeds and SBT in accordance with a prospective protocol. For the present analysis, we selected 95 of 277 patients with LGG, in whom SBT was applied to treat progressive (43 patients) or recurrent (52 patients) tumor after resection. At 24 months after seed implantation, the tumor response rate was 35.9%, and the tumor control rate was 97.3%. The median progression-free-survival (PFS) duration after SBT was 52.7 ± 7.1 months. Five-year and 10-year PFS probabilities were 43.4% and 10.7%, respectively. Malignant tumor transformation, the diagnosis "astrocytoma," and tumor volume >20 mL were significantly associated with reduced PFS. Tumor progression or relapse after SBT (53 of 95 patients) was treated with tumor resection, a second SBT, chemotherapy, and/or radiotherapy. The median overall survival duration (from the first diagnosis of LGG until the patient's last contact) was 245.0 ± 4.9 months. Patients still under observation after seed implantation had a median follow-up time of 156.4 ± 55.7 months. Perioperative transient morbidity was 1.1%, and the frequency of permanent morbidity caused by SBT was 3.3%. In conclusion, SBT of recurrent or progressive LGG after resection located in functionally critical brain areas has high local efficacy and comparably low morbidity. Referred to individually adopted glioma treatment concepts SBT provides a reasonably long PFS, thus improving overall survival. In selected patients, SBT can lead to delays in the application of chemotherapy and/or radiotherapy.

  12. AAPM recommendations on dose prescription and reporting methods for permanent interstitial brachytherapy for prostate cancer: report of Task Group 137.

    PubMed

    Nath, Ravinder; Bice, William S; Butler, Wayne M; Chen, Zhe; Meigooni, Ali S; Narayana, Vrinda; Rivard, Mark J; Yu, Yan

    2009-11-01

    During the past decade, permanent radioactive source implantation of the prostate has become the standard of care for selected prostate cancer patients, and the techniques for implantation have evolved in many different forms. Although most implants use 125I or 103Pd sources, clinical use of 131Cs sources has also recently been introduced. These sources produce different dose distributions and irradiate the tumors at different dose rates. Ultrasound was used originally to guide the planning and implantation of sources in the tumor. More recently, CT and/or MR are used routinely in many clinics for dose evaluation and planning. Several investigators reported that the tumor volumes and target volumes delineated from ultrasound, CT, and MR can vary substantially because of the inherent differences in these imaging modalities. It has also been reported that these volumes depend critically on the time of imaging after the implant. Many clinics, in particular those using intraoperative implantation, perform imaging only on the day of the implant. Because the effects of edema caused by surgical trauma can vary from one patient to another and resolve at different rates, the timing of imaging for dosimetry evaluation can have a profound effect on the dose reported (to have been delivered), i.e., for the same implant (same dose delivered), CT at different timing can yield different doses reported. Also, many different loading patterns and margins around the tumor volumes have been used, and these may lead to variations in the dose delivered. In this report, the current literature on these issues is reviewed, and the impact of these issues on the radiobiological response is estimated. The radiobiological models for the biological equivalent dose (BED) are reviewed. Starting with the BED model for acute single doses, the models for fractionated doses, continuous low-dose-rate irradiation, and both homogeneous and inhomogeneous dose distributions, as well as tumor cure

  13. AAPM recommendations on dose prescription and reporting methods for permanent interstitial brachytherapy for prostate cancer: Report of Task Group 137

    SciTech Connect

    Nath, Ravinder; Bice, William S.; Butler, Wayne M.; Chen Zhe; Meigooni, Ali S.; Narayana, Vrinda; Rivard, Mark J.; Yu Yan

    2009-11-15

    During the past decade, permanent radioactive source implantation of the prostate has become the standard of care for selected prostate cancer patients, and the techniques for implantation have evolved in many different forms. Although most implants use {sup 125}I or {sup 103}Pd sources, clinical use of {sup 131}Cs sources has also recently been introduced. These sources produce different dose distributions and irradiate the tumors at different dose rates. Ultrasound was used originally to guide the planning and implantation of sources in the tumor. More recently, CT and/or MR are used routinely in many clinics for dose evaluation and planning. Several investigators reported that the tumor volumes and target volumes delineated from ultrasound, CT, and MR can vary substantially because of the inherent differences in these imaging modalities. It has also been reported that these volumes depend critically on the time of imaging after the implant. Many clinics, in particular those using intraoperative implantation, perform imaging only on the day of the implant. Because the effects of edema caused by surgical trauma can vary from one patient to another and resolve at different rates, the timing of imaging for dosimetry evaluation can have a profound effect on the dose reported (to have been delivered), i.e., for the same implant (same dose delivered), CT at different timing can yield different doses reported. Also, many different loading patterns and margins around the tumor volumes have been used, and these may lead to variations in the dose delivered. In this report, the current literature on these issues is reviewed, and the impact of these issues on the radiobiological response is estimated. The radiobiological models for the biological equivalent dose (BED) are reviewed. Starting with the BED model for acute single doses, the models for fractionated doses, continuous low-dose-rate irradiation, and both homogeneous and inhomogeneous dose distributions, as well as

  14. Evaluation of health-related quality of life in patients with prostate cancer after treatment with radical retropubic prostatectomy and permanent prostate brachytherapy.

    PubMed

    Dragićević, Svetomir; Naumović, Tamara; Soldatović, Ivan

    2010-01-01

    The aims of this study were to evaluate the health-related quality of life (HRQOL) and make the treatment decision less difficult. Between 2007 and 2009 radical retropubic prostatectomy (RRP) was performed in 96 patients and permanent prostate brachytherapy (PPB) in 88 patients at our hospital. The general and disease-specific HRQOL was measured using two instruments, the Medical Outcome Study 8-Item Short-Form Health Survey (SF-8) and the expanded prostate index composite (EPIC). Comparing RRP and PPB, there were significant differences in all scores except for general health in the 1st month after treatment which had the same score in both groups. The baseline quality of life scores in physical function (p < 0.05), physical role (p < 0.01), social functioning (p < 0.01), emotional role (p < 0.01) and mental health (p < 0.01) showed significant differences between the group and were better in the PPB group than in the RRP group. The physical component summary score in the PPB group was better than in the RRP group in the 1st month (p < 0.01) but recovered up to 3 months in the RRP group. The urinary bother and irritative/obstructive scores in the 1st month were worse from baseline in both groups (p < 0.05) and remained significantly worse up to 6 months in the PPB group than in the RRP group where these scores recovered within 3 months. The urinary incontinence score in the RRP group was still worse than in the PPB group up to 12 months (p < 0.01). Bowel function and bother were significantly better in the RRP group at 3 (p < 0.05) and 6 months (p < 0.01) than in the PPB group where bowel function at 12 months was worse than at baseline and in the RRP group. Sexual function (p < 0.01) and sexual bother were better in the PPB group and did not change until 12 months. The difference in disease-specific quality of life has become clearer using EPIC. As with other published studies, our results provide important information that will therefore be useful for selecting

  15. Comparison of Dosimetric and Biologic Effective Dose Parameters for Prostate and Urethra Using {sup 131}Cs and {sup 125}I for Prostate Permanent Implant Brachytherapy

    SciTech Connect

    Sahgal, Arjun; Jabbari, Siavash; Chen, Josephine; Pickett, Barbie; Roach, Mack; Weinberg, Vivian; Hsu, I-C.; Pouliot, Jean

    2008-09-01

    Purpose: To compare the urethral and prostate absolute and biologic effective doses (BEDs) for {sup 131}Cs and {sup 125}I prostate permanent implant brachytherapy (PPI). Methods and Materials: Eight previously implanted manually planned {sup 125}I PPI patients were replanned manually with {sup 131}Cs, and re-planned using Inverse Planning Simulated Annealing. {sup 131}Cs activity and the prescribed dose (115 Gy) were determined from that recommended by IsoRay. The BED was calculated for the prostate and urethra using an {alpha}/{beta} ratio of 2 and was also calculated for the prostate using an {alpha}/{beta} ratio of 6 and a urethral {alpha}/{beta} ratio of 2. The primary endpoints of this study were the prostate D{sub 90} BED (pD{sub 90}BED) and urethral D{sub 30} BED normalized to the maximal potential prostate D{sub 90} BED (nuD{sub 30}BED). Results: The manual plan comparison ({alpha}/{beta} = 2) yielded no significant difference in the prostate D{sub 90} BED (median, 192 Gy{sub 2} for both isotopes). No significant difference was observed for the nuD{sub 30}BED (median, 199 Gy{sub 2} and 202 Gy{sub 2} for {sup 125}I and {sup 131}Cs, respectively). For the inverse planning simulated annealing plan comparisons ({alpha}/{beta} 2), the prostate D{sub 90} BED was significantly lower with {sup 131}Cs than with {sup 125}I (median, 177 Gy{sub 2} vs. 187 Gy{sub 2}, respectively; p = 0.01). However, the nuD{sub 30}BED was significantly greater with {sup 131}Cs than with {sup 125}I (median, 192 Gy{sub 2} vs. 189 Gy{sub 2}, respectively; p = 0.01). Both the manual and the inverse planning simulated annealing plans resulted in a significantly lower prostate D{sub 90} BED (p = 0.01) and significantly greater nuD{sub 30}BED for {sup 131}Cs (p = 0.01), compared with {sup 125}I, when the prostate {alpha}/{beta} ratio was 6 and the urethral {alpha}/{beta} ratio was 2. Conclusion: This report highlights the controversy in comparing the dose to both the prostate and the organs

  16. Vibro-acoustography with 1.75D ultrasound array transducer for detection and localization of permanent prostate brachytherapy seeds: ex vivo study

    NASA Astrophysics Data System (ADS)

    Mehrmohammadi, Mohammad; Alizad, Azra; Kinnick, Randall R.; Davis, Brian J.; Fatemi, Mostafa

    2013-03-01

    Effective brachytherapy procedures require precise placement of radioactive seeds in the prostate. Currently, transrectal ultrasound (TRUS) imaging is one of the main intraoperative imaging modalities to assist physicians in placement of brachytherapy seeds. However, the seed detection rate with TRUS is poor mainly because ultrasound imaging is highly sensitive to variations in seed orientation. The purpose of this study is to investigate the abilities of a new acoustic radiation force imaging modality, vibro-acoustography (VA), equipped with a 1.75D array transducer and implemented on a customized clinical ultrasound scanner, to image and localize brachytherapy seeds in prostatic tissue. To perform experiments, excised cadaver prostate specimens were implanted with dummy brachytherapy seeds, and embedded in tissue mimicking gel to simulate the properties of the surrounding soft tissues. The samples were scanned using the VA system and the resulting VA signals were used to reconstruct VA images at several depths inside the tissue. To further evaluate the performance of VA in detecting seeds, X-ray computed tomography (CT) images of the same tissue sample, were obtained and used as a gold-standard to compare the number of seeds detected by the two methods. Our results indicate that VA is capable of imaging of brachytherapy seeds with accuracy and high contrast, and can detect a large percentage of the seeds implanted within the tissue samples.

  17. Brachytherapy versus prostatectomy in localized prostate cancer: Results of a French multicenter prospective medico-economic study

    SciTech Connect

    Buron, Catherine; Le Vu, Beatrice; Cosset, Jean-Marc; Peiffert, Didier; Delannes, Martine; Flam, Thierry; Guerif, Stephane; Salem, Naji; Chauveinc, Laurent; Livartowski, Alain . E-mail: alain.livartowski@curie.net

    2007-03-01

    Purpose: To prospectively compare health-related quality of life (HRQOL), patient-reported treatment-related symptoms, and costs of iodine-125 permanent implant interstitial brachytherapy (IB) with those of radical prostatectomy (RP) during the first 2 years after these treatments for localized prostate cancer. Methods and Materials: A total of 435 men with localized low-risk prostate cancer, from 11 French hospitals, treated with IB (308) or RP (127), were offered to complete the European Organization for Research and Treatment of Cancer core Quality of Life Questionnaire QLQ-C30 version 3 (EORTC QLQ-C30) and the prostate cancer specific EORTC QLQ-PR25 module before and at the end of treatment, 2, 6, 12, 18, and 24 months after treatment. Repeated measures analysis of variance and analysis of covariance were conducted on HRQOL changes. Comparative cost analysis covered initial treatment, hospital follow-up, outpatient and production loss costs. Results: Just after treatment, the decrease of global HRQOL was less pronounced in the IB than in the RP group, with a 13.5 points difference (p < 0.0001). A difference slightly in favor of RP was observed 6 months after treatment (-7.5 points, p = 0.0164) and was maintained at 24 months (-8.2 points, p = 0.0379). Impotence and urinary incontinence were more pronounced after RP, whereas urinary frequency, urgency, and urination pain were more frequent after IB. Mean societal costs did not differ between IB ( Euro 8,019 at T24) and RP ( Euro 8,715 at T24, p = 0.0843) regardless of the period. Conclusions: This study suggests a similar cost profile in France for IB and RP but with different HRQOL and side effect profiles. Those findings may be used to tailor localized prostate cancer treatments to suit individual patients' needs.

  18. Portal Vein Stenting Combined with Iodine-125 Seeds Endovascular Implantation Followed by Transcatheter Arterial Chemoembolization for Treatment of Hepatocellular Carcinoma Patients with Portal Vein Tumor Thrombus

    PubMed Central

    Zhou, Tanyang; Zhu, Tongyin; Zhang, Yuelin; Nie, Chunhui; Ai, Jing; Zhou, Guanhui; Zhang, Aibin; Dong, Meng-Jie; Wang, Wei-Lin

    2016-01-01

    Aim was to assess the therapeutic value of portal vein stenting (PVS) combined with iodine-125 seed (125I seed) strand endovascular implantation followed by transcatheter arterial chemoembolization (TACE) for treating patients with hepatocellular carcinoma (HCC) and portal vein tumor thrombus (PVTT). This was a retrospective study of 34 patients aged 29–81 years, diagnosed HCC with PVTT, and treated with PVS combined with 125I seed strand endovascular implantation followed by TACE between January 2012 and August 2014. Survival, stent patency, technical success rate, complications related to the procedure, and adverse events were recorded. The technical success rate was 100%. No serious procedure-related adverse event was recorded. The median survival was 147 days. The cumulative survival rates and stent patency rates at 90, 180, and 360 days were 94.1%, 61.8%, and 32.4% and 97.1% (33/34), 76.9% (24/34), and 29.4% (10/34), respectively. PVS combined with 125I seed strand endovascular implantation followed by TACE is feasible for patients with HCC and PVTT. It resulted in appropriate survival and stent patency, with no procedure-related adverse effects. PMID:27999793

  19. Plastic optical fibre sensor for in-vivo radiation monitoring during brachytherapy

    NASA Astrophysics Data System (ADS)

    Woulfe, P.; Sullivan, F. J.; Lewis, E.; O'Keeffe, S.

    2015-09-01

    An optical fibre sensor is presented for applications in real-time in-vivo monitoring of the radiation dose a cancer patient receives during seed implantation in Brachytherapy. The sensor is based on radioluminescence whereby radiation sensitive scintillation material is embedded in the core of a 1mm plastic optical fibre. Three scintillation materials are investigated: thallium-doped caesium iodide (CsI:Tl), terbium-doped gadolinium oxysulphide (Gd2O2S:Tb) and europium-doped lanthanum oxysulphide (La2O2S:Eu). Terbium-doped gadolinium oxysulphide was identified as being the most suitable scintillator and further testing demonstrates its measureable response to different activities of Iodine-125, the radio-active source commonly used in Brachytherapy for treating prostate cancer.

  20. [Endovascular implantation of iodine-125 seeds strand and portal vein stenting followed by transcatheter arterial chemoembolization combined therapy with sorafenib for hepatocellular carcinoma with main portal vein tumor thrombus].

    PubMed

    Li, W W; Dai, Z Y; Wan, H G; Yao, L Z; Zhu, J; Li, C L; Wang, X J; Pan, J; Chen, L Z

    2016-06-21

    To compare the therapeutic effect of portal vein stenting and endovascular implantation of iodine-125 seeds strand followed by transcatheter arterial chemoembolization combined with or without sorafenib in patients for hepatocellular carcinoma (HCC) with main portal vein tumor thrombus (MPVTT). A total of 53 patients with HCC complicated by MPVTT who received portal vein stenting and endovascular implantation of iodine-125 seeds strand followed by transcatheter arterial chemoembolization combined without (group A, n=38) or with (group B, n=15) sorafenib in Affiliated Yancheng Hospital of Southeast University Medical College during January 2010 and August 2015 were analyzed retropectively.Overal survival, progress free survival and procedure-related adverse event were compared between the two groups. The technical success rate was 100% for placement of (125)I seeds strand and stent in the obstructed main portal vein.No serious procedure-related adverse events occurred. Median survival time of group A and B were 12.1 and 14.8 months, respectively (P=0.037). Additionally, Median progress free survival time of group A and B were 2.8 and 4.0 months, respectively (P=0.002). Endovascular implantation of iodine-125 seeds strand and portal vein stenting followed by transcatheter arterial chemoembolization combined with sorafenib could improve the survival time, the progress free survival time of patients with HCC complicated by MPVTT.

  1. Brachytherapy for prostate cancer: summary of American Brachytherapy Society recommendations.

    PubMed

    Nag, S

    2000-05-01

    This article summarizes recent American Brachytherapy Society (ABS) recommendations for permanent prostate brachytherapy. The ABS recommends treating patients with high probability of organ-confined disease with brachytherapy alone. Brachytherapy candidates with a significant risk of extraprostatic extension should be treated with supplemental external beam radiation therapy (EBRT). The recommended prescription doses for monotherapy are 145 Gy for (125)I and 125 Gy for (103)Pd. The corresponding boost doses (after 40 to 50 Gy EBRT) are 110 Gy and 100 Gy, respectively. The ABS recommends that post-implant dosimetry should be performed on all patients undergoing permanent prostate brachytherapy for optimal patient care. A dose-volume histogram (DVH) of the prostate should be performed and the D(90) (dose to 90% of the prostate gland) reported by all centers. Additionally, the D(80) D(100), the fractional V(80), V(90), V(100), V(150), V(200) (ie, the percentage of prostate volume receiving 80%, 90%, 100%, 150%, and 200% of the prescribed dose, respectively), the rectal and urethral doses should be reported and ultimately correlated with clinical outcome in the research environment. On-line, real-time dosimetry, the effects of dose heterogeneity, and the effects of tissue heterogeneity need further investigation.

  2. An analysis of intraoperative versus post-operative dosimetry with CT, CT-MRI fusion and XMR for the evaluation of permanent prostate brachytherapy implants.

    PubMed

    Acher, Peter; Puttagunta, Srikanth; Rhode, Kawal; Morris, Stephen; Kinsella, Janette; Gaya, Andrew; Dasgupta, Prokar; Deehan, Charles; Beaney, Ronald; Popert, Rick; Keevil, Stephen

    2010-08-01

    To assess the agreement between intraoperative and post-operative dosimetry and to identify factors that influence dose calculations of prostate brachytherapy implants. Patients treated with prostate brachytherapy implants underwent post-operative CT and XMR (combined X-ray and MR) imaging. Dose-volume histograms were calculated from CT, XMR and CT-MR fusion data and compared with intraoperative values for two observers. Multiple linear regression models assessed the influences of intraoperative D90, gland oedema, gland volume, source loss and migration, and implanted activity/volume prostate on post-operative D90. Forty-nine patients were studied. The mean D90 differences (95% confidence limits) between intraoperative and post-operative CT, XMR and CT-MR fusion assessments were: 11 Gy (-22, 45), 18 Gy (-13, 49) and 20 Gy (-17, 58) for Observer 1; and 15 Gy (-34, 63), 13 Gy (-29, 55) and 14 Gy (-27, 54) for Observer 2. Multiple linear regression modelling showed that the observed oedema and intraoperative D90 were significant independent variables for the prediction of post-operative D90 values for both observers using all modalities. This is the first study to report Bland-Altman agreement analysis between intraoperative and post-operative dosimetry. Agreement is poor. Post-operative dosimetry is dependent on the intraoperative D90 and the subjectively outlined gland volume. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  3. Long-term Results of the UCSF-LBNL Randomized Trial: Charged Particle With Helium Ion Versus Iodine-125 Plaque Therapy for Choroidal and Ciliary Body Melanoma

    SciTech Connect

    Mishra, Kavita K.; Quivey, Jeanne M.; Daftari, Inder K.; Weinberg, Vivian; Cole, Tia B.; Patel, Kishan; Castro, Joseph R.; Phillips, Theodore L.; Char, Devron H.

    2015-06-01

    Purpose: Relevant clinical data are needed given the increasing national interest in charged particle radiation therapy (CPT) programs. Here we report long-term outcomes from the only randomized, stratified trial comparing CPT with iodine-125 plaque therapy for choroidal and ciliary body melanoma. Methods and Materials: From 1985 to 1991, 184 patients met eligibility criteria and were randomized to receive particle (86 patients) or plaque therapy (98 patients). Patients were stratified by tumor diameter, thickness, distance to disc/fovea, anterior extension, and visual acuity. Tumors close to the optic disc were included. Local tumor control, as well as eye preservation, metastases due to melanoma, and survival were evaluated. Results: Median follow-up times for particle and plaque arm patients were 14.6 years and 12.3 years, respectively (P=.22), and for those alive at last follow-up, 18.5 and 16.5 years, respectively (P=.81). Local control (LC) for particle versus plaque treatment was 100% versus 84% at 5 years, and 98% versus 79% at 12 years, respectively (log rank: P=.0006). If patients with tumors close to the disc (<2 mm) were excluded, CPT still resulted in significantly improved LC: 100% versus 90% at 5 years and 98% versus 86% at 12 years, respectively (log rank: P=.048). Enucleation rate was lower after CPT: 11% versus 22% at 5 years and 17% versus 37% at 12 years, respectively (log rank: P=.01). Using Cox regression model, likelihood ratio test, treatment was the most important predictor of LC (P=.0002) and eye preservation (P=.01). CPT was a significant predictor of prolonged disease-free survival (log rank: P=.001). Conclusions: Particle therapy resulted in significantly improved local control, eye preservation, and disease-free survival as confirmed by long-term outcomes from the only randomized study available to date comparing radiation modalities in choroidal and ciliary body melanoma.

  4. Dosimetry of a thyroid uptake detected in seed migration survey following a patient's iodine-125 prostate implant and in vitro measurements of intentional seed leakages

    SciTech Connect

    Chen Qinsheng; Russell, John L. Jr.; Macklis, Roger R.; Weinhous, Martin S.; Blair, Henry F.

    2006-07-15

    As a quality control procedure, a post-implant seed migration survey has been accomplished on 340 prostate cancer patients since November 2001. Pulmonary seed embolization and intracardiac seed embolization have been detected. A case of thyroid uptake due to leaking iodine-125 (I-125) sources was also seized. In order to determine the dose to the thyroid, a dosimetry method was developed to link in vivo measurements and the cumulated dose to the thyroid. The calculated source leakage half-life in the case was approximately 15 days based on the measurements and the estimated cumulated dose to thyroid was 204 cGy. It is concluded that one seed was leaking. In order to verify the in vivo measurements, intentional in vitro seed leakage tests were performed. A seed was cut open and placed in a sealed glass container filled with a given volume of saline. The I-125 concentration in the saline was subsequently measured over a period of six months. Consistent in vivo and in vitro results were obtained. Recent incidents of seed leaks reported from other centers have drawn practitioners' attention to this problem. In order to make the measurements more useful, the seed leakage tests were expanded to include I-125 seeds from six other vendors. The results show that the leakage half-lives of those seeds varied from nine days to a half-year. Two seed models demonstrated least leakage. Since the measurements lasted for six months, the escape of iodine resulted from oxidation of iodide in the saline was a concern for the measurement accuracy. As a reference, another set of leakage tests were performed by adding sodium thiosulfate salt (Na{sub 2}S{sub 2}O{sub 3}{center_dot}5H{sub 2}O) to the saline. Sodium thiosulfate is a reducing agent that prevents the conversion of iodide to iodate so as to minimize I-125 evaporation. As a result, significantly shortened leakage half-lives were observed in this group. Seed agitation was also performed and no significant deviations of the

  5. Clinical application and validation of an iterative forward projection matching algorithm for permanent brachytherapy seed localization from conebeam-CT x-ray projections

    PubMed Central

    Pokhrel, Damodar; Murphy, Martin J.; Todor, Dorin A.; Weiss, Elisabeth; Williamson, Jeffrey F.

    2010-01-01

    Purpose: To experimentally validate a new algorithm for reconstructing the 3D positions of implanted brachytherapy seeds from postoperatively acquired 2D conebeam-CT (CBCT) projection images. Methods: The iterative forward projection matching (IFPM) algorithm finds the 3D seed geometry that minimizes the sum of the squared intensity differences between computed projections of an initial estimate of the seed configuration and radiographic projections of the implant. In-house machined phantoms, containing arrays of 12 and 72 seeds, respectively, are used to validate this method. Also, four 103Pd postimplant patients are scanned using an ACUITY digital simulator. Three to ten x-ray images are selected from the CBCT projection set and processed to create binary seed-only images. To quantify IFPM accuracy, the reconstructed seed positions are forward projected and overlaid on the measured seed images to find the nearest-neighbor distance between measured and computed seed positions for each image pair. Also, the estimated 3D seed coordinates are compared to known seed positions in the phantom and clinically obtained VariSeed planning coordinates for the patient data. Results: For the phantom study, seed localization error is (0.58±0.33) mm. For all four patient cases, the mean registration error is better than 1 mm while compared against the measured seed projections. IFPM converges in 20–28 iterations, with a computation time of about 1.9–2.8 min∕iteration on a 1 GHz processor. Conclusions: The IFPM algorithm avoids the need to match corresponding seeds in each projection as required by standard back-projection methods. The authors’ results demonstrate ∼1 mm accuracy in reconstructing the 3D positions of brachytherapy seeds from the measured 2D projections. This algorithm also successfully localizes overlapping clustered and highly migrated seeds in the implant. PMID:20964229

  6. WE-A-17A-09: Exploiting Electromagnetic Technologies for Real-Time Seed Drop Position Validation in Permanent Implant Brachytherapy

    SciTech Connect

    Racine, E; Hautvast, G; Binnekamp, D; Beaulieu, L

    2014-06-15

    Purpose: To report on preliminary results validating the performance of a specially designed LDR brachytherapy needle prototype possessing both electromagnetic (EM) tracking and seed drop detection abilities. Methods: An EM hollow needle prototype has been designed and constructed in collaboration with research partner Philips Healthcare. The needle possesses conventional 3D tracking capabilities, along with a novel seed drop detection mechanism exploiting local changes of electromagnetic properties generated by the passage of seeds in the needle's embedded sensor coils. These two capabilities are exploited by proprietary engineering and signal processing techniques to generate seed drop position estimates in real-time treatment delivery. The electromagnetic tracking system (EMTS) used for the experiment is the NDI Aurora Planar Field Generator. The experiment consisted of dropping a total of 35 seeds in a prismatic agarose phantom, and comparing the 3D seed drop positions of the EMTS to those obtained by an image analysis of subsequent micro-CT scans. Drop position error computations and statistical analysis were performed after a 3D registration of the two seed distributions. Results: Of the 35 seeds dropped in the phantom, 32 were properly detected by the needle prototype. Absolute drop position errors among the detected seeds ranged from 0.5 to 4.8 mm with mean and standard deviation values of 1.6 and 0.9 mm, respectively. Error measurements also include undesirable and uncontrollable effects such as seed motion upon deposition. The true accuracy performance of the needle prototype is therefore underestimated. Conclusion: This preliminary study demonstrates the potential benefits of EM technologies in detecting the passage of seeds in a hollow needle as a means of generating drop position estimates in real-time treatment delivery. Such tools could therefore represent a potentially interesting addition to existing brachytherapy protocols for rapid dosimetry

  7. Repeated iodine-125 seed implantations combined with external beam radiotherapy for the treatment of locally recurrent or metastatic stage III/IV non-small cell lung cancer: a retrospective study.

    PubMed

    Li, Wei; Dan, Gang; Jiang, Jianqing; Zheng, Yifeng; Zheng, Xiushan; Deng, Dan

    2016-09-13

    Recurrent or metastatic lung cancer is difficult to manage. This retrospective study aimed to assess the efficacy of repeated iodine-125 seed implantations combined with external beam radiotherapy (EBRT) for locally recurrent or metastatic stage-III/IV non-small cell lung cancer (NSCLC). Eighteen previously treated stage-III/IV NSCLC patients with local or metastatic recurrences underwent 1-to-3 iodine-125 implantations. Six of these patients received palliative EBRT and six patients received combined chemotherapy using gemcitabine and cisplatin. Near-term treatment efficacy was evaluated 3 months after seed implantation by comparing changes in tumor size on computed tomography images; the evaluated outcomes were complete response, partial response, stable disease, and local tumor control rate. Long-term efficacy was assessed based on 1- and 2-year survival rates. Patients were followed up for 6 to 50 months. The overall (i.e., complete + partial) response rate was 87.4 %. The local control rates after the first, second, and third years were 94.1, 58.8 and 41.2 %, respectively. The results of this study demonstrated that repeated implantation of radioactive particles combined with EBRT is a safe treatment that effectively controlled local recurrence and metastasis of stage III/IV NSCLC.

  8. Brachytherapy for Patients With Prostate Cancer: American Society of Clinical Oncology/Cancer Care Ontario Joint Guideline Update.

    PubMed

    Chin, Joseph; Rumble, R Bryan; Kollmeier, Marisa; Heath, Elisabeth; Efstathiou, Jason; Dorff, Tanya; Berman, Barry; Feifer, Andrew; Jacques, Arthur; Loblaw, D Andrew

    2017-03-27

    Purpose To jointly update the Cancer Care Ontario guideline on brachytherapy for patients with prostate cancer to account for new evidence. Methods An Update Panel conducted a targeted systematic literature review and identified more recent randomized controlled trials comparing dose-escalated external beam radiation therapy (EBRT) with brachytherapy in men with prostate cancer. Results Five randomized controlled trials provided the evidence for this update. Recommendations For patients with low-risk prostate cancer who require or choose active treatment, low-dose rate brachytherapy (LDR) alone, EBRT alone, and/or radical prostatectomy (RP) should be offered to eligible patients. For patients with intermediate-risk prostate cancer choosing EBRT with or without androgen-deprivation therapy, brachytherapy boost (LDR or high-dose rate [HDR]) should be offered to eligible patients. For low-intermediate risk prostate cancer (Gleason 7, prostate-specific antigen < 10 ng/mL or Gleason 6, prostate-specific antigen, 10 to 20 ng/mL), LDR brachytherapy alone may be offered as monotherapy. For patients with high-risk prostate cancer receiving EBRT and androgen-deprivation therapy, brachytherapy boost (LDR or HDR) should be offered to eligible patients. Iodine-125 and palladium-103 are each reasonable isotope options for patients receiving LDR brachytherapy; no recommendation can be made for or against using cesium-131 or HDR monotherapy. Patients should be encouraged to participate in clinical trials to test novel or targeted approaches to this disease. Additional information is available at www.asco.org/Brachytherapy-guideline and www.asco.org/guidelineswiki .

  9. Comparison of Intraoperatively Built Custom Linked Seeds Versus Loose Seed Gun Applicator Technique Using Real-Time Intraoperative Planning for Permanent Prostate Brachytherapy

    SciTech Connect

    Zauls, A. Jason; Ashenafi, Michael S.; Onicescu, Georgiana; Clarke, Harry S.; Marshall, David T.

    2011-11-15

    Purpose: To report our dosimetric results using a novel push-button seed delivery system that constructs custom links of seeds intraoperatively. Methods and Materials: From 2005 to 2007, 43 patients underwent implantation using a gun applicator (GA), and from 2007 to 2008, 48 patientsunderwent implantation with a novel technique allowing creation of intraoperatively built custom links of seeds (IBCL). Specific endpoint analyses were prostate D90% (pD90%), rV100% > 1.3 cc, and overall time under anesthesia. Results: Final analyses included 91 patients, 43 GA and 48 IBCL. Absolute change in pD90% ({Delta}pD90%) between intraoperative and postoperative plans was evaluated. Using GA method, the {Delta}pD90% was -8.1Gy and -12.8Gy for I-125 and Pd-103 implants, respectively. Similarly, the IBCL technique resulted in a {Delta}pD90% of -8.7Gy and -9.8Gy for I-125 and Pd-103 implants, respectively. No statistically significant difference in {Delta}pD90% was found comparing methods. The GA method had two intraoperative and 10 postoperative rV100% >1.3 cc. For IBCL, five intraoperative and eight postoperative plans had rV100% >1.3 cc. For GA, the mean time under anesthesia was 75 min and 87 min for Pd-103 and I-125 implants, respectively. For IBCL, the mean time was 86 and 98 min for Pd-103 and I-125. There was a statistical difference between the methods when comparing mean time under anesthesia. Conclusions: Dosimetrically relevant endpoints were equivalent between the two methods. Currently, time under anesthesia is longer using the IBCL technique but has decreased over time. IBCL is a straightforward brachytherapy technique that can be implemented into clinical practice as an alternative to gun applicators.

  10. 10-Year Experience With I-125 Prostate Brachytherapy at the Princess Margaret Hospital: Results for 1,100 Patients

    SciTech Connect

    Crook, Juanita; Borg, Jette; Evans, Andrew; Toi, Ants; Saibishkumar, E.P.; Fung, Sharon; Ma, Clement

    2011-08-01

    Purpose: To report outcomes for 1,111 men treated with iodine-125 brachytherapy (BT) at a single institution. Methods and Materials: A total of 1,111 men (median age, 63) were treated with iodine-125 prostate BT for low- or intermediate-risk prostate cancer between March 1999 and November 2008. Median prostate-specific antigen (PSA) level was 5.4 ng/ml (range, 0.9-26.1). T stage was T1c in 66% and T2 in 34% of patients. Gleason score was 6 in 90.1% and 7 or 8 in 9.9% of patients. Neoadjuvant hormonal therapy (2-6 months course) was used in 10.1% of patients and combined external radiotherapy (45 Gy) with BT (110 Gy) in 4.1% (n = 46) of patients. Univariate and multivariate Cox proportional hazards were used to determine predictors of failure. Results: Median follow-up was 42 months (range, 6-114), but for biochemical freedom from relapse, a minimum PSA test follow-up of 30 months was required (median 54; n = 776). There were 27 failures, yielding an actuarial 7-year disease-free survival rate of 95.2% (96 at risk beyond 84 months). All failures underwent repeat 12-core transrectal ultrasound -guided biopsies, confirming 8 local failures. On multivariate analysis, Gleason score was the only independent predictor of failure (p = 0.001; hazard ratio, 4.8 (1.9-12.4). Median International Prostate Symptom score from 12 to 108 months ranged between 3 and 9. Of the men reporting baseline potency, 82.8% retained satisfactory erectile function beyond 5 years. Conclusion: Iodine-125 prostate BT is a highly effective treatment option for favorable- and intermediate-risk prostate cancer and is associated with maintenance of good urinary and erectile functions.

  11. Dosimetric characteristics of the new RadioCoil{sup TM} {sup 103}Pd wire line source for use in permanent brachytherapy implants

    SciTech Connect

    Meigooni, A.S.; Zhang, H.; Clark, J.R.; Rachabatthula, V.; Koona, R.A.

    2004-11-01

    Recently, a novel linear brachytherapy source in the form of a coiled wire has become available for use in interstitial implants of various treatment sites such as prostate gland. This source type employs a design completely different from that of most 'seed' sources currently on the market, one which improves upon or eliminates several common problems with such sources. Dosimetric characteristics of these sources with active lengths 0.5 cm to 5.0 cm were determined for clinical application. For 0.5 cm and 1.0 cm active length sources, the dose rate constant, radial dose function, and two-dimensional (2D) anisotropy function were experimentally and theoretically determined following the updated AAPM Task Group 43 (TG-43U1) recommendations. Radial dose functions and/or 'along-away' matrix functions were also obtained for sources with active lengths 2.0 cm to 5.0 cm. Measurements were performed with LiF thermoluminescent dosimeters in Solid Water{sup TM} phantoms. Measured data was compared to Monte Carlo simulated data in Solid Water{sup TM} utilizing the PTRAN code, version 7.43. After finding the data to be in agreement, Monte Carlo calculations were performed in liquid water to obtain clinically applicable dosimetric data as per TG-43U1 recommendations. The results indicated the dose rate constant of the 0.5 cm long RadioCoil{sup TM103}Pd source in Solid Water{sup TM} to be 0.641 cGy h{sup -1} U{sup -1} when measured, and 0.636 cGy h{sup -1} U{sup -1} when simulated by Monte Carlo. The calculated dose rate constant in liquid water was found to be 0.650 cGy h{sup -1} U{sup -1}. These values are comparable to other commercially available sources. Complete dosimetric data and simulation results are described in this paper. Per TG-43U1, clinical treatment planning systems should utilize the values reported for liquid water.

  12. Tumor-height regression rate after brachytherapy between choroidal melanoma gene expression profile classes: effect of controlling for tumor height.

    PubMed

    Gupta, Kishan; McCannel, Colin A; Kamrava, Mitchell; Lamb, James; Almanzor, Robert D; McCannel, Tara A

    2016-07-01

    To evaluate the relationship between choroidal melanoma regression rate and its gene expression profile class after iodine-125 brachytherapy at 3 and 6 months, controlling for baseline tumor height. Patients from October 2012 to January 2015 at a single Ophthalmic Oncology Center who had undergone iodine-125 brachytherapy for the treatment of choroidal melanoma and who had a gene expression profile test result obtained from intraoperative fine-needle aspiration biopsy at the time of plaque surgery were retrospectively reviewed. Baseline patient and tumor characteristics were obtained, including tumor height and gene expression profile test result. Tumor height at 3 and 6 months following treatment was obtained. Regression rate was analyzed with two-way analysis of variance to class type and baseline pre-operative tumor height. Class 2 patients were matched to class 1 patients by tumor height and resulting distributions of paired regression rate differences were compared. A total of 114 patients were studied. When preoperative tumor height was controlled for in the comparative analysis, neither group of patients at 3 or 6 months had a significant dependency between gene expression profile class and tumor regression rate. Additionally, class 1 and class 2 patients matched for pre-operative tumor height did not express different regression rates. Our study adds to a growing body of evidence that tumor regression rate does not necessarily depend on gene expression profile class type in choroidal melanoma after brachytherapy at 3 and 6 months when controlling for baseline tumor height.

  13. Cold spot mapping inferred from MRI at time of failure predicts biopsy-proven local failure after permanent seed brachytherapy in prostate cancer patients: Implications for focal salvage brachytherapy

    PubMed Central

    Crehange, Gilles; Krishnamurthy, Devan; Cunha, J. Adam; Pickett, Barby; Kurhanewicz, John; Hsu, I-Chow; Gottschalk, Alexander R.; Shinohara, Katsuto; Roach, Mack; Pouliot, Jean

    2014-01-01

    Background and purpose To establish a method to evaluate dosimetry at the time of primary prostate permanent implant (pPPI) using MRI of the shrunken prostate at the time of failure (tf). To compare cold spot mapping with sextant-biopsy mapping at tf. Material and methods Twenty-four patients were referred for biopsy-proven local failure (LF) after pPPI. Multiparametric MRI and combined-sextant biopsy with a central review of the pathology at tf were systematically performed. A model of the shrinking pattern was defined as a Volumetric Change Factor (VCF) as a function of time from time of pPPI (t0). An isotropic expansion to both prostate volume (PV) and seed position (SP) coordinates determined at tf was performed using a validated algorithm using the VCF. Results pPPI CT-based evaluation (at 4 weeks) vs. MR-based evaluation: Mean D90% was 145.23 ± 19.16 Gy [100.0–167.5] vs. 85.28 ± 27.36 Gy [39–139] (p = 0.001), respectively. Mean V100% was 91.6 ± 7.9% [70–100%] vs. 73.1 ± 13.8% [55–98%] (p = 0.0006), respectively. Seventy-seven per cent of the pathologically positive sextants were classified as cold. Conclusions Patients with biopsy-proven LF had poorer implantation quality when evaluated by MRI several years after implantation. There is a strong relationship between microscopic involvement at tf and cold spots. PMID:24231238

  14. Evaluation of (iodine-125)N,N,N'-trimethyl-N'-(2-hydroxy-3-methyl-5-iodobenzyl)-1,3- propanediamine lung uptake using an isolated-perfused lung model

    SciTech Connect

    Slosman, D.O.; Brill, A.B.; Polla, B.S.; Alderson, P.O.

    1987-02-01

    Lung uptake of N,N,N'-trimethyl-N'-(2-Hydroxy-3-methyl-5-iodobenzyl)-1,3- propanediamine (HIPDM) has been reported, but the mechanism of this process has not yet been established. Thus, single-pass (/sup 125/I)HIPDM accumulation was studied in rat lungs perfused with a Krebs-Ringer bicarbonate buffer containing 4.5% bovine albumin. Iodine-125 HIPDM lung accumulation was monitored by the percent of extraction per gram of lung tissue. Iodine-125 HIPDM lung uptake did not appear to occur by simple diffusion. As the time of perfusion was increased from 2 to 15 min, the rate of uptake of 2 microM (/sup 125/I)HIPDM decreased by 40%. During a 2-min perfusion, 98.6% +/- 6.7 (n = 8) extraction was observed with 2 microM (/sup 125/I)HIPDM, but only 38% +/- 2.0 (n = 3) was extracted when the (/sup 125/I)HIPDM concentration was 1 mM. The addition of 1 mM chlorpromazine, propranolol or imipramine also decreased (/sup 125/I)HIPDM lung uptake to 43.0% +/- 1.5, 51.4% +/- 2.2, and 49.8% +/- 0.8, respectively, (each n = 4 - 6, p less than 0.001). Cold (4 degrees C) had little effect on pulmonary accumulation (77.7% +/- 7.4, n = 5, p less than 0.01), and the addition of ouabain or the use of sodium-free medium had no effect. Thus, pulmonary (/sup 125/I)HIPDM accumulation does not appear to occur by sodium-dependent active transport. Rather, its uptake appears to be similar to the uptake of other basic amines, such as propranolol and imipramine, which are known to bind by physico-chemical interactions to pulmonary endothelial cell membranes and reflect pulmonary vascular surface area.

  15. Optical fibre luminescence sensor for real-time LDR brachytherapy dosimetry

    NASA Astrophysics Data System (ADS)

    Woulfe, P.; Sullivan, F. J.; O'Keeffe, S.

    2016-05-01

    An optical fibre sensor for monitoring low dose radiation is presented. The sensor is based on a scintillation material embedded within the optical fibre core, which emits visible light when exposed to low level ionising radiation. The incident level of ionising radiation can be determined by analysing the optical emission. An optical fibre sensor is presented, based on radioluminescence whereby radiation sensitive scintillation material, terbium doped gadolinium oxysulphide (Gd2O2S:Tb), is embedded in a cavity of 250μm of a 500μm plastic optical fibre. The sensor is designed for in-vivo monitoring of the radiation dose during radio-active seed implantation for brachytherapy, in prostate cancer treatment, providing oncologists with real-time information of the radiation dose to the target area and/or nearby critical structures. The radiation from the brachytherapy seeds causes emission of visible light from the scintillation material through the process of radioluminescence, which penetrates the fibre, propagating along the optical fibre for remote detection using a multi-pixel photon counter. The sensor demonstrates a high sensitivity to Iodine-125, the radioactive source most commonly used in brachytherapy for treating prostate cancer.

  16. Image fusion analysis of volumetric changes after interstitial low-dose-rate iodine-125 irradiation of supratentorial low-grade gliomas.

    PubMed

    Julow, Jeno; Major, Tibor; Mangel, László; Bajzik, Gábor; Viola, Arpad

    2007-04-01

    The aim of this study was to compare the volumes of tumor necrosis, reactive zone and edema with the three-dimensional dose distributions after brachytherapy treatments of gliomas. The investigation was performed an average of 14.2 months after low-dose-rate (125)I interstitial irradiation of 25 inoperable low-grade gliomas. The prescribed dose was 50-60 Gy to the tumor surface. Dose planning and image fusion were performed with the BrainLab-Target 1.19 software. In the CT/ MRI images, the "triple ring" (tumor necrosis, reactive ring and edema) developing after the interstitial irradiation of the brain tumors was examined. The images with the triple ring were fused with the planning images, and the isodose curves were superimposed on them. The volumes of the three regions were measured. The average dose at the necrosis border was determined from the isodose distribution. For quantitative assessment of the dose distributions, the dose nonuniformity ratio (DNR), homogeneity index (HI), coverage index (CI) and conformal index (COIN) were calculated. The relative volumes of the different parts of the triple ring after the interstitial irradiation compared to the reference dose volume were the following: necrosis, 40.9%, reactive zone, 47.1%, and edema, 367%. The tumor necrosis developed at 79.1 Gy on average. The average DNR, HI, CI and COIN were 0.45, 0.24, 0.94 and 0.57, respectively. The image fusion analysis of the volume of tumor necrosis, reactive ring and edema caused by interstitial irradiation and their correlation with the dose distribution provide valuable information for patient follow-up, treatment options, and effects and side effects of radio therapy.

  17. Long-Term Results of a Prospective, Phase II Study of Long-Term Androgen Ablation, Pelvic Radiotherapy, Brachytherapy Boost, and Adjuvant Docetaxel in Patients With High-Risk Prostate Cancer

    SciTech Connect

    DiBiase, Steven J.; Hussain, Arif; Kataria, Ritesh; Amin, Pradip; Bassi, Sunakshi; Dawson, Nancy; Kwok, Young

    2011-11-01

    Purpose: We report the long-term results of a prospective, Phase II study of long-term androgen deprivation (AD), pelvic radiotherapy (EBRT), permanent transperineal prostate brachytherapy boost (PB), and adjuvant docetaxel in patients with high-risk prostate cancer. Methods and Materials: Eligibility included biopsy-proven prostate adenocarcinoma with the following: prostate-specific antigen (PSA) > 20 ng/ml; or Gleason score of 7 and a PSA >10 ng/ml; or any Gleason score of 8 to 10; or stage T2b to T3 irrespective of Gleason score or PSA. Treatment consisted of 45 Gy of pelvic EBRT, followed 1 month later by PB with either iodine-125 or Pd-103. One month after PB, patients received three cycles of docetaxel chemotherapy (35 mg/m{sup 2} per week, Days 1, 8, and 15 every 28 days). All patients received 2 years of AD. Biochemical failure was defined as per the Phoenix definition (PSA nadir + 2). Results: From August 2000 to March 2004, 42 patients were enrolled. The median overall and active follow-ups were 5.6 years (range, 0.9-7.8 years) and 6.3 years (range, 4-7.8 years), respectively. Grade 2 and 3 acute genitourinary (GU) and gastrointestinal (GI) toxicities were 50.0% and 14.2%, respectively, with no Grade 4 toxicities noted. Grade 3 and 4 acute hematologic toxicities were 19% and 2.4%, respectively. Of the patients, 85.7% were able to complete the planned multimodality treatment. The 5- and 7-year actuarial freedom from biochemical failures rates were 89.6% and 86.5%, and corresponding rates for disease-free survival were 76.2% and 70.4%, respectively. The 5- and 7-year actuarial overall survival rates were 83.3% and 80.1%, respectively. The 5- and 7-year actuarial rates of late Grade 2 GI/GU toxicity (no Grade 3-5) was 7.7%. Conclusions: The trimodality approach of using 2 years of AD, external radiation, brachytherapy, and upfront docetaxel in high-risk prostate cancer is well tolerated, produces encouraging long-term results, and should be validated in a

  18. [Prostate cancer brachytherapy].

    PubMed

    Pommier, P; Guérif, S; Peiffert, D; Créhange, G; Hannoun-Lévi, J-M; de Crevoisier, R

    2016-09-01

    Prostate brachytherapy techniques are described, concerning both Iodine 125 high dose rate brachytherapy. The following parts are presented: brachytherapy indications, technical description, immediate postoperative management and post-treatment evaluation, and 4 to 6 weeks as well as long-term follow-up. Copyright © 2016. Published by Elsevier SAS.

  19. Equivalent Biochemical Control and Improved Prostate-Specific Antigen Nadir After Permanent Prostate Seed Implant Brachytherapy Versus High-Dose Three-Dimensional Conformal Radiotherapy and High-Dose Conformal Proton Beam Radiotherapy Boost

    SciTech Connect

    Jabbari, Siavash; Weinberg, Vivian K.; Shinohara, Katsuto; Speight, Joycelyn L.; Gottschalk, Alexander R.; Hsu, I.-C.; Pickett, Barby; McLaughlin, Patrick W.; Sandler, Howard M.; Roach, Mack

    2010-01-15

    Purpose: Permanent prostate implant brachytherapy (PPI), three-dimensional conformal radiotherapy (3D-CRT), and conformal proton beam radiotherapy (CPBRT) are used in the treatment of localized prostate cancer, although no head-to-head trials have compared these modalities. We studied the biochemical control (biochemical no evidence of disease [bNED]) and prostate-specific antigen (PSA) nadir achieved with contemporary PPI, and evaluated it against 3D-CRT and CPBRT. Patients and Methods: A total of 249 patients were treated with PPI at the University of California, San Francisco, and the outcomes were compared with those from a 3D-CRT cohort and the published results of a high-dose CPBRT boost (CPBRTB) trial. For each comparison, subsets of the PPI cohort were selected with patient and disease criteria similar to those of the reference group. Results: With a median follow-up of 5.3 years, the bNED rate at 5 and 7 years achieved with PPI was 92% and 86%, respectively, using the American Society for Therapeutic Radiology and Oncology (ASTRO) definition, and 93% using the PSA nadir plus 2 ng/mL definition. Using the ASTRO definition, a 5-year bNED rate of 78% was achieved for the 3D-CRT patients compared with 94% for a comparable PPI subset and 93% vs. 92%, respectively, using the PSA nadir plus 2 ng/mL definition. The median PSA nadir for patients treated with PPI and 3D-CRT was 0.10 and 0.40 ng/mL, respectively (p < .0001). For the CPBRT comparison, the 5-year bNED rate after a CPBRTB was 91% using the ASTRO definition vs. 93% for a similar group of PPI patients. A greater proportion of PPI patients achieved a lower PSA nadir compared with those achieved in the CPBRTB trial (PSA nadir <=0.5 ng/mL, 91% vs. 59%, respectively). Conclusion: We have demonstrated excellent outcomes in low- to intermediate-risk patients treated with PPI, suggesting at least equivalent 5-year bNED rates and a greater proportion of men achieving lower PSA nadirs compared with 3D-CRT or

  20. Comparing the RTOG/EORTC and LENT-SOMA scoring systems for the evaluation of late skin toxicity after (125)I seed brachytherapy for parotid gland cancer.

    PubMed

    Mao, Ming-Hui; Feng, Zhien; Li, Hua; Qin, Li-Zheng; Li, Jian-Hua; Huang, Xin; Xing, Ru-Dong; Zhang, Jie; Zhang, Jian-Guo; Han, Zheng-Xue

    The Radiation Therapy Oncology Group (RTOG) and Late Effects Normal Tissue Task Force-Subjective, Objective, Management and Analytic (LENT-SOMA) scoring systems were compared for grading late skin effects after iodine-125 seed brachytherapy in parotid gland cancer patients. A total of 109 patients diagnosed with parotid gland carcinoma were treated postoperatively with iodine-125 seed brachytherapy at a dose of 100-120 Gy. After 6-24 months of followup, telangiectasia, skin pigmentation, atrophy, fibrosis, and ulceration were scored according to both RTOG and LENT-SOMA scale criteria. The strength of correlation between the scores and the interobserver variability were calculated. Of 109 patients, 22.9% had telangiectasia; 78.9%, pigmentation; 28.4%, fibrosis; 4.6%, edema; 0.9%, ulceration; 37.6%, retraction and/or atrophy; 22.9%, sensation change; and 11%, scaliness and/or roughness. Compared with RTOG, LENT-SOMA criteria resulted in the upgrading of pigmentation in 17% of cases, the downgrading of all instances of telangiectasia and the downgrading of one instance of Grade 4 ulceration to Grade 3. Between the two scales, fibrosis and atrophy correlated well (Spearman ρ, 0.992, 0.986). An additional 229 side effects were observed using LENT-SOMA criteria. The LENT-SOMA scale was more accurate than the RTOG scale for the evaluation of late skin and subcutaneous toxicity. The downgrading of telangiectasia and upgrading of pigmentation with the LENT-SOMA scale reflected the patients' conditions better than the scores obtained with the RTOG scale. The assessment of fibrosis and atrophy correlated well between the two scales. The use of the sum of the individual scores of the LENT-SOMA is therefore advocated. The addition of decreased sweating and the removal of the alopecia (scalp) metric should be considered to standardize the reporting of late radiation morbidity. Copyright © 2017 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  1. A Monte Carlo investigation of lung brachytherapy treatment planning

    NASA Astrophysics Data System (ADS)

    Sutherland, J. G. H.; Furutani, K. M.; Thomson, R. M.

    2013-07-01

    Iodine-125 (125I) and Caesium-131 (131Cs) brachytherapy have been used in conjunction with sublobar resection to reduce the local recurrence of stage I non-small cell lung cancer compared with resection alone. Treatment planning for this procedure is typically performed using only a seed activity nomogram or look-up table to determine seed strand spacing for the implanted mesh. Since the post-implant seed geometry is difficult to predict, the nomogram is calculated using the TG-43 formalism for seeds in a planar geometry. In this work, the EGSnrc user-code BrachyDose is used to recalculate nomograms using a variety of tissue models for 125I and 131Cs seeds. Calculated prescription doses are compared to those calculated using TG-43. Additionally, patient CT and contour data are used to generate virtual implants to study the effects that post-implant deformation and patient-specific tissue heterogeneity have on perturbing nomogram-derived dose distributions. Differences of up to 25% in calculated prescription dose are found between TG-43 and Monte Carlo calculations with the TG-43 formalism underestimating prescription doses in general. Differences between the TG-43 formalism and Monte Carlo calculated prescription doses are greater for 125I than for 131Cs seeds. Dose distributions are found to change significantly based on implant deformation and tissues surrounding implants for patient-specific virtual implants. Results suggest that accounting for seed grid deformation and the effects of non-water media, at least approximately, are likely required to reliably predict dose distributions in lung brachytherapy patients.

  2. Comparison of methods for calculating glomerular filtration rate: Technetium-99m-DTPA scintigraphic analysis, protein-free and whole-plasma clearance of technetium-99m-DTPA and iodine-125-iothalamate clearance

    SciTech Connect

    Goates, J.J.; Morton, K.A.; Whooten, W.W.; Greenberg, H.E.; Datz, F.L.; Handy, J.E.; Scuderi, A.J.; Haakenstad, A.O.; Lynch, R.E. )

    1990-04-01

    True glomerular filtration rate (GFR) was measured in normal volunteers and in patients with normal and impaired renal function by the iothalamate clearance (IC) method of Sigman. Within 24 hr, GFR was also determined by two other methods: technetium-99m- ({sup 99m}Tc) DTPA scintigraphic analysis (SA) utilizing a modification of the Gates computer program, and by measuring disappearance of {sup 99m}Tc-DTPA from whole plasma (WPC) and from protein-free ultrafiltered plasma (PFPC). Determinations of GFR by IC and by PFPC methods were virtually identical (mean absolute error 5.36 ml/min, r = 0.99, p greater than 0.05). GFRs measured in protein-free, ultrafiltered plasma differed significantly from those obtained from whole plasma only in sicker patients and in those taking multiple medications (in whom alterations in protein-binding of DTPA may be seen). The SA method correlated less well with the iodine-125-({sup 125}I) IC method than did either the protein-free or whole-plasma clearance methods (mean absolute error 32.36 ml/min, r = 0.74, p less than 0.05). However, the SA method provided useful information with respect to differential (split) renal function.

  3. Stereotactic interstitial brachytherapy of malignant astrocytomas with remarks on postimplantation computed tomographic appearance

    SciTech Connect

    Willis, B.K.; Heilbrun, M.P.; Sapozink, M.D.; McDonald, P.R.

    1988-09-01

    Seventeen patients were treated with stereotactically implanted high activity iodine-125 seeds, 12 patients for recurrent malignant astrocytomas (Protocol I) and 5 patients for newly diagnosed glioblastomas (Protocol II). Total radiation dosage to the recurrent tumors in Protocol I, including prior external beam irradiation, averaged 13,500 cGy. In the follow-up period of 6 to 50 months, the survival rate was 93% at 6 months, 60% at 12 months, 50% at 18 months, and 38% at 24 months after implantation. In Protocol II, brachytherapy was used as an interstitial radiation boost to the conventional treatment of newly diagnosed glioblastomas. External beam therapy and interstitial brachytherapy provided 11,000 cGy to these tumors. In the follow-up period of 15 to 27 months, there was a 100% survival at 12 months, 75% at 18 months, and 25% at 24 months after implantation. Eight of our 17 patients required reoperation for persistent or recurrent mass lesions at 6 to 15 months postimplantation; 7 were found to harbor masses of radionecrosis containing nests of anaplastic astrocytes; 1 had frank tumor recurrence. Median survival in this group of patients requiring reoperation was 18.7 months postimplantation. In a review of postimplantation computed tomographic scans, significant mass effect and crossover of hypodensity or enhancement into the corpus callosum or opposite hemisphere were found to have prognostic significance; persistent areas of contrast enhancement and excessive peritumoral hypodensity did not.

  4. Brachytherapy Application With In Situ Dose Painting Administered by Gold Nanoparticle Eluters

    SciTech Connect

    Sinha, Neeharika; Cifter, Gizem; Sajo, Erno; Kumar, Rajiv; Sridhar, Srinivas; Nguyen, Paul L.; Cormack, Robert A.; Makrigiorgos, G. Mike; Ngwa, Wilfred

    2015-02-01

    Purpose: Recent studies show promise that administering gold nanoparticles (GNP) to tumor cells during brachytherapy could significantly enhance radiation damage to the tumor. A new strategy proposed for sustained administration of the GNP in prostate tumors is to load them into routinely used brachytherapy spacers for customizable in situ release after implantation. This in silico study investigated the intratumor biodistribution and corresponding dose enhancement over time due to GNP released from such GNP-loaded brachytherapy spacers (GBS). Method and Materials: An experimentally determined intratumoral diffusion coefficient (D) for 10-nm nanoparticles was used to estimate D for other sizes by using the Stokes-Einstein equation. GNP concentration profiles, obtained using D, were then used to calculate the corresponding dose enhancement factor (DEF) for each tumor voxel, using dose painting-by-numbers approach, for times relevant to the considered brachytherapy sources' lifetimes. The investigation was carried out as a function of GNP size for the clinically applicable low-dose-rate brachytherapy sources iodine-125 (I-125), palladium-103 (Pd-103), and cesium-131 (Cs-131). Results: Results showed that dose enhancement to tumor voxels and subvolumes during brachytherapy can be customized by varying the size of GNP released or eluted from the GBS. For example, using a concentration of 7 mg/g GNP, significant DEF (>20%) could be achieved 5 mm from a GBS after 5, 12, 25, 46, 72, 120, and 195 days, respectively, for GNP sizes of 2, 5, 10, 20, 30, and 50 nm and for 80 nm when treating with I-125. Conclusions: Analyses showed that using Cs-131 provides the highest dose enhancement to tumor voxels. However, given its relatively longer half-life, I-125 presents the most flexibility for customizing the dose enhancement as a function of GNP size. These findings provide a useful reference for further work toward development of potential new brachytherapy application with

  5. Prostate brachytherapy - discharge

    MedlinePlus

    Implant therapy - prostate cancer - discharge; Radioactive seed placement - discharge ... You had a procedure called brachytherapy to treat prostate cancer. Your treatment lasted 30 minutes or more, depending ...

  6. Acute urinary morbidity after a permanent 125I implantation for localized prostate cancer.

    PubMed

    Ohga, Saiji; Nakamura, Katsumasa; Shioyama, Yoshiyuki; Tatsugami, Katsunori; Sasaki, Tomonari; Nonoshita, Takeshi; Yoshitake, Tadamasa; Asai, Kaori; Hirata, Hideki; Naito, Seiji; Honda, Hiroshi

    2014-11-01

    We evaluated the predictive factors of acute urinary morbidity (AUM) after prostate brachytherapy. From November 2005 to January 2007, 62 patients with localized prostate cancer were treated using brachytherapy. The (125)Iodine ((125)I) seed-delivering method was a modified peripheral pattern. The prescribed dose was 144 Gy. Urinary morbidity was scored at 3 months after implantation. The clinical and treatment parameters were analysed for correlation with AUM. In particular, in this study, Du90 (the minimal dose received by 90% of the urethra), Dup90 (the minimal dose received by 90% of the proximal half of the urethra on the bladder side) and Dud90 (the minimal dose received by 90% of the distal half of the urethra on the penile side) were analysed. We found that 43 patients (69.4%) experienced acute urinary symptoms at 3 months after implantation. Of them, 40 patients had Grade 1 AUM, one patient had Grade 2 pain, and two patients had Grade 2 urinary frequency. None of the patients had ≥Grade 3. Univariate and multivariate analysis revealed that Du90 and Dup90 were significantly correlated with AUM. In this study, Du90 and Dup90 were the most significant predictors of AUM after prostate brachytherapy.

  7. The dosimetry of brachytherapy-induced erectile dysfunction

    SciTech Connect

    Merrick, Gregory S.; Butler, Wayne M

    2003-12-31

    There is emerging evidence that brachytherapy-induced erectile dysfunction (ED) is technique-related and may be minimized by careful attention to source placement. Herein, we review the relationship between radiation doses to the prostate gland/surrounding structures and the development of brachytherapy-induced ED. The permanent prostate brachytherapy literature was reviewed using MEDLINE searches to ensure completeness. Although the site-specific structure associated with brachytherapy-induced ED remains unknown, there is an increasing body of data implicating the proximal penis. With day 0 CT-based dosimetry, the dose to 50% (D{sub 50}) and 25% (D{sub 25}) of the bulb of the penis should be maintained below 40% and 60% mPD, respectively, while the crura D{sub 50} should be maintained below 28% mPD to maximize post-brachytherapy potency. To date, there is no data to suggest that either radiation doses to the neurovascular bundles or choice of isotope is associated with brachytherapy-induced ED, while conflicting data has been reported regarding radiation dose to the prostate and the use of supplemental external beam radiation therapy. Although the etiology of brachytherapy-induced ED is likely multifactorial, the available data supports the proximal penis as an important site-specific structure. Refinements in implant technique, including preplanning and intraoperative seed placement, will result in lower radiation doses to the proximal penis with potential improvement in potency preservation.

  8. Radiation pneumonitis caused by a migrated brachytherapy seed lodged in the lung.

    PubMed

    Miura, Noriyoshi; Kusuhara, Yoshito; Numata, Kousaku; Shirato, Akitomi; Hashine, Katsuyoshi; Sumiyoshi, Yoshiteru; Kataoka, Masaaki; Takechi, Shinsuke

    2008-09-01

    We report a case of radiation pneumonitis caused by a migrated seed lodged in the lung after prostate brachytherapy. A 71-year-old man underwent transperineal interstitial permanent prostate brachytherapy for localized prostate cancer. On the day after brachytherapy, a routine postimplant chest X-ray revealed migration of one seed to the lower lobe of the left lung. After 1 month, pulmonary opacities were observed in the left lower lobe but not near the seed. He was diagnosed with bacterial pneumonia, and antibiotic therapy was commenced. Two months after brachytherapy, the patient's symptoms, laboratory data and pulmonary opacities improved; however, an abnormal shadow (consolidation) developed around the migrated seed. Lung consolidation disappeared almost completely 12 months after brachytherapy without any medical treatment. The abnormal shadow probably represented radiation pneumonitis. To the best of our knowledge, this is the first report of radiation pneumonitis caused by a migrated brachytherapy seed in the lung.

  9. [Valorisation of brachytherapy and medico-economic considerations].

    PubMed

    Pommier, P; Morelle, M; Millet-Lagarde, F; Peiffert, D; Gomez, F; Perrier, L

    2013-04-01

    Economic data in the literature for brachytherapy are still sparse and heterogeneous, with few controlled prospective studies and a perspective most often limited to those of the provider (health insurances). Moreover, these observation and conclusions are difficult to generalize in France. The prospective health economic studies performed in France in the framework of a national program to sustain innovative and costly therapies (STIC program) launched by the French cancer national institute are therefore of most importance. With the exception of prostate brachytherapy with permanent seeds, the valorisation of the brachytherapy activity by the French national health insurance does not take into account the degree of complexity and the real costs supported by health institutions (i.e. no specific valorisation for 3D image-based treatment planning and dose optimization and for the use of pulsed dose rate brachytherapy).

  10. Advancements in brachytherapy.

    PubMed

    Tanderup, Kari; Ménard, Cynthia; Polgar, Csaba; Lindegaard, Jacob Christian; Kirisits, Christian; Pötter, Richard

    2017-01-15

    Brachytherapy is a radiotherapy modality associated with a highly focal dose distribution. Brachytherapy treats the cancer tissue from the inside, and the radiation does not travel through healthy tissue to reach the target as with external beam radiotherapy techniques. The nature of brachytherapy makes it attractive for boosting limited size target volumes to very high doses while sparing normal tissues. Significant developments over the last decades have increased the use of 3D image guided procedures with the utilization of CT, MRI, US and PET. This has taken brachytherapy to a new level in terms of controlling dose and demonstrating excellent clinical outcome. Interests in focal, hypofractionated and adaptive treatments are increasing, and brachytherapy has significant potential to develop further in these directions with current and new treatment indications.

  11. Brachytherapy in lip cancer.

    PubMed

    Rovirosa-Casino, Angeles; Planas-Toledano, Isabel; Ferre-Jorge, Jorge; Oliva-Díez, José María; Conill-Llobet, Carlos; Arenas-Prat, Meritxell

    2006-05-01

    Lip cancer is one of the most prevalent skin tumours of the head and neck. The characteristics of the tumour relate to their exophyitic growth in an area of easy visual acces which allows their diagnosis in early stages. As a result, there is a better prognosis with the present treatments. In early stages the treatment can be performed by surgery or by brachytherapy, and the results are similar on local control; nevertheless brachytherapy offers the best functional and esthetic results. We are reporting on a review of the literature in relation to indications, techniques and results of brachytherapy for lip cancer.

  12. Prostate brachytherapy in Ghana: our initial experience

    PubMed Central

    Yarney, Joel; Vanderpuye, Verna; Akpakli, Evans; Tagoe, Samuel; Sasu, Evans

    2016-01-01

    Purpose This study presents the experience of a brachytherapy team in Ghana with a focus on technology transfer and outcome. The team was initially proctored by experienced physicians from Europe and South Africa. Material and methods A total of 90 consecutive patients underwent either brachytherapy alone or brachytherapy in combination with external beam radiotherapy for prostate carcinoma between July 2008 and February 2014 at Korle Bu Teaching Hospital, Accra, Ghana. Patients were classified as low-risk, intermediate, and high-risk according to the National Comprehensive Cancer Network (NCCN) criteria. All low-risk and some intermediate risk group patients were treated with seed implantation alone. Some intermediate and all high-risk group patients received brachytherapy combined with external beam radiotherapy. Results The median patient age was 64.0 years (range 46-78 years). The median follow-up was 58 months (range 18-74 months). Twelve patients experienced biochemical failure including one patient who had evidence of metastatic disease and died of prostate cancer. Freedom from biochemical failure rates for low, intermediate, and high-risk cases were 95.4%, 90.9%, and 70.8%, respectively. Clinical parameters predictive of biochemical outcome included: clinical stage, Gleason score, and risk group. Pre-treatment prostate specific antigen (PSA) was not a statistically significant predictor of biochemical failure. Sixty-nine patients (76.6%) experienced grade 1 urinary symptoms in the form of frequency, urgency, and poor stream. These symptoms were mostly self-limiting. Four patients needed catheterization for urinary retention (grade 2). One patient developed a recto urethral fistula (grade 3) following banding for hemorrhoids. Conclusions Our results compare favorably with those reported by other institutions with more extensive experience. We believe therefore that, interstitial permanent brachytherapy can be safely and effectively performed in a

  13. [Brachytherapy for sarcomas].

    PubMed

    Ducassou, A; Haie-Méder, C; Delannes, M

    2016-10-01

    The standard of care for local treatment for extremities soft tissue sarcomas relies on conservative surgery combined with external beam radiotherapy. Brachytherapy can be realized instead of external beam radiotherapy in selected cases, or more often used as a boost dose on a limited volume on the area at major risk of relapse, especially if a microscopic positive resection is expected. Close interaction and communication between radiation oncologists and surgeons are mandatory at the time of implantation to limit the risk of side effects. Long-term results are available for low-dose rate brachytherapy. Nowadays, pulsed dose rate or high-dose-rate brachytherapy are more often used. Brachytherapy for paediatric sarcomas is rare, and has to be managed in reference centres.

  14. Delivery systems for brachytherapy.

    PubMed

    de la Puente, Pilar; Azab, Abdel Kareem

    2014-10-28

    Brachytherapy is described as the short distance treatment of cancer with a radioactive isotope placed on, in, or near the lesions or tumor to be treated. The main advantage of brachytherapy compared with external beam radiation (EBR) is the improved localized delivery of dose to the target volume of interest, thus normal tissue irradiation is reduced. The precise and targeted nature of brachytherapy provides a number of key benefits for the effective treatment of cancer such as efficacy, minimized risk of side effects, short treatment times, and cost-effectiveness. Brachytherapy devices have yielded promising results in preclinical and clinical studies. However, brachytherapy can only be used in localized and relatively small tumors. Although the introduction of new delivery devices allows the treatment of more complex tumor sites, with wider range of dose rate for improving treatment efficacy and reduction of side effects, a better understanding about the safety, efficacy, and accuracy of these systems is required, and further development of new techniques is warranted. Therefore, this review focuses on the delivery devices for brachytherapy and their application in prostate, breast, brain, and other tumor sites.

  15. ALGEBRA: ALgorithm for the heterogeneous dosimetry based on GEANT4 for BRAchytherapy.

    PubMed

    Afsharpour, H; Landry, G; D'Amours, M; Enger, S; Reniers, B; Poon, E; Carrier, J-F; Verhaegen, F; Beaulieu, L

    2012-06-07

    Task group 43 (TG43)-based dosimetry algorithms are efficient for brachytherapy dose calculation in water. However, human tissues have chemical compositions and densities different than water. Moreover, the mutual shielding effect of seeds on each other (interseed attenuation) is neglected in the TG43-based dosimetry platforms. The scientific community has expressed the need for an accurate dosimetry platform in brachytherapy. The purpose of this paper is to present ALGEBRA, a Monte Carlo platform for dosimetry in brachytherapy which is sufficiently fast and accurate for clinical and research purposes. ALGEBRA is based on the GEANT4 Monte Carlo code and is capable of handling the DICOM RT standard to recreate a virtual model of the treated site. Here, the performance of ALGEBRA is presented for the special case of LDR brachytherapy in permanent prostate and breast seed implants. However, the algorithm is also capable of handling other treatments such as HDR brachytherapy.

  16. ALGEBRA: ALgorithm for the heterogeneous dosimetry based on GEANT4 for BRAchytherapy

    NASA Astrophysics Data System (ADS)

    Afsharpour, H.; Landry, G.; D'Amours, M.; Enger, S.; Reniers, B.; Poon, E.; Carrier, J.-F.; Verhaegen, F.; Beaulieu, L.

    2012-06-01

    Task group 43 (TG43)-based dosimetry algorithms are efficient for brachytherapy dose calculation in water. However, human tissues have chemical compositions and densities different than water. Moreover, the mutual shielding effect of seeds on each other (interseed attenuation) is neglected in the TG43-based dosimetry platforms. The scientific community has expressed the need for an accurate dosimetry platform in brachytherapy. The purpose of this paper is to present ALGEBRA, a Monte Carlo platform for dosimetry in brachytherapy which is sufficiently fast and accurate for clinical and research purposes. ALGEBRA is based on the GEANT4 Monte Carlo code and is capable of handling the DICOM RT standard to recreate a virtual model of the treated site. Here, the performance of ALGEBRA is presented for the special case of LDR brachytherapy in permanent prostate and breast seed implants. However, the algorithm is also capable of handling other treatments such as HDR brachytherapy.

  17. Plaque Brachytherapy for Uveal Melanoma: A Vision Prognostication Model

    SciTech Connect

    Khan, Niloufer; Khan, Mohammad K.; Bena, James; Macklis, Roger; Singh, Arun D.

    2012-11-01

    Purpose: To generate a vision prognostication model after plaque brachytherapy for uveal melanoma. Methods and Materials: All patients with primary single ciliary body or choroidal melanoma treated with iodine-125 or ruthenium-106 plaque brachytherapy between January 1, 2005, and June 30, 2010, were included. The primary endpoint was loss of visual acuity. Only patients with initial visual acuity better than or equal to 20/50 were used to evaluate visual acuity worse than 20/50 at the end of the study, and only patients with initial visual acuity better than or equal to 20/200 were used to evaluate visual acuity worse than 20/200 at the end of the study. Factors analyzed were sex, age, cataracts, diabetes, tumor size (basal dimension and apical height), tumor location, and radiation dose to the tumor apex, fovea, and optic disc. Univariate and multivariable Cox proportional hazards were used to determine the influence of baseline patient factors on vision loss. Kaplan-Meier curves (log rank analysis) were used to estimate freedom from vision loss. Results: Of 189 patients, 92% (174) were alive as of February 1, 2011. At presentation, visual acuity was better than or equal to 20/50 and better than or equal to 20/200 in 108 and 173 patients, respectively. Of these patients, 44.4% (48) had post-treatment visual acuity of worse than 20/50 and 25.4% (44) had post-treatment visual acuity worse than 20/200. By multivariable analysis, increased age (hazard ratio [HR] of 1.01 [1.00-1.03], P=.05), increase in tumor height (HR of 1.35 [1.22-1.48], P<.001), and a greater total dose to the fovea (HR of 1.01 [1.00-1.01], P<.001) were predictive of vision loss. This information was used to develop a nomogram predictive of vision loss. Conclusions: By providing a means to predict vision loss at 3 years after treatment, our vision prognostication model can be an important tool for patient selection and treatment counseling.

  18. Dosimetric analysis and comparison of IMRT and HDR brachytherapy in treatment of localized prostate cancer.

    PubMed

    Murali, V; Kurup, P G G; Mahadev, P; Mahalakshmi, S

    2010-04-01

    Radical radiotherapy is one of the options for the management of prostate cancer. In external beam therapy, 3D conformal radiotherapy (3DCRT) and intensity modulated radiotherapy (IMRT) are the options for delivery of increased radiation dose, as vital organs are very close to the prostate and a higher dose to these structures leads to an increased toxicity. In brachytherapy, low dose rate brachytherapy with permanent implant of radioactive seeds and high dose rate brachytherapy (HDR) with remote after loaders are available. A dosimetric analysis has been made on IMRT and HDR brachytherapy plans. Ten cases from each IMRT and HDR brachytherapy have been taken for the study. The analysis includes comparison of conformity and homogeneity indices, D100, D95, D90, D80, D50, D10 and D5 of the target. For the organs at risk (OAR), namely rectum and bladder, V100, V90 and V50 are compared. In HDR brachytherapy, the doses to 1 cc and 0.1 cc of urethra have also been studied. Since a very high dose surrounds the source, the 300% dose volumes in the target and within the catheters are also studied in two plans, to estimate the actual volume of target receiving dose over 300%. This study shows that the prescribed dose covers 93 and 92% of the target volume in IMRT and HDR brachytherapy respectively. HDR brachytherapy delivers a much lesser dose to OAR, compared to the IMRT. For rectum, the V50 in IMRT is 34.0cc whilst it is 7.5cc in HDR brachytherapy. With the graphic optimization tool in HDR brachytherapy planning, the dose to urethra could be kept within 120% of the target dose. Hence it is concluded that HDR brachytherapy may be the choice of treatment for cancer of prostate in the early stage.

  19. Paraspinal tumors: Techniques and results of brachytherapy

    SciTech Connect

    Armstrong, J.G.; Fass, D.E.; Bains, M.; Mychalczak, B.; Nori, D.; Arbit, E.; Martini, N.; Harrison, L.B. )

    1991-04-01

    Because of their proximity to nerve roots and the spinal cord, it is frequently difficult to achieve complete resection of paraspinal tumors. We have used brachytherapy in an attempt to prevent local recurrence and its associated neurological sequelae. This report analyzes our experience with 35 patients to determine the feasibility, optimal techniques, and efficacy of this approach. The tumor types were non small-cell lung cancer (18), sarcomas (9), and other tumor types (8). Temporary, single plane implants using Ir-192 (median minimum peripheral dose 3000 cGy) were used in 21 patients, and permanent I-125 implants were used in 14 cases (median matched peripheral dose 12,500 cGy). Local control was achieved in 51% (18/35). However, local control was poor when lung cancers were implanted and in cases where the dura was exposed. Radiation myelitis did not occur despite the combined effects of previous external beam radiotherapy (N = 21) and brachytherapy. Our experience demonstrates that combined surgery and paraspinal brachytherapy can be performed with acceptable toxicity and is reasonably effective in preventing local relapse and its neurologic sequelae, particularly for tumors other than lung cancers.

  20. MRI-guided brachytherapy

    PubMed Central

    Tanderup, Kari; Viswanathan, Akila; Kirisits, Christian; Frank, Steven J.

    2014-01-01

    The application of MRI-guided brachytherapy has demonstrated significant growth during the last two decades. Clinical improvements in cervix cancer outcomes have been linked to the application of repeated MRI for identification of residual tumor volumes during radiotherapy. This has changed clinical practice in the direction of individualized dose administration, and mounting evidence of improved clinical outcome with regard to local control, overall survival as well as morbidity. MRI-guided prostate HDR and LDR brachytherapy has improved the accuracy of target and organs-at-risk (OAR) delineation, and the potential exists for improved dose prescription and reporting for the prostate gland and organs at risk. Furthermore, MRI-guided prostate brachytherapy has significant potential to identify prostate subvolumes and dominant lesions to allow for dose administration reflecting the differential risk of recurrence. MRI-guided brachytherapy involves advanced imaging, target concepts, and dose planning. The key issue for safe dissemination and implementation of high quality MRI-guided brachytherapy is establishment of qualified multidisciplinary teams and strategies for training and education. PMID:24931089

  1. Dosimetric audit in brachytherapy

    PubMed Central

    Bradley, D A; Nisbet, A

    2014-01-01

    Dosimetric audit is required for the improvement of patient safety in radiotherapy and to aid optimization of treatment. The reassurance that treatment is being delivered in line with accepted standards, that delivered doses are as prescribed and that quality improvement is enabled is as essential for brachytherapy as it is for the more commonly audited external beam radiotherapy. Dose measurement in brachytherapy is challenging owing to steep dose gradients and small scales, especially in the context of an audit. Several different approaches have been taken for audit measurement to date: thimble and well-type ionization chambers, thermoluminescent detectors, optically stimulated luminescence detectors, radiochromic film and alanine. In this work, we review all of the dosimetric brachytherapy audits that have been conducted in recent years, look at current audits in progress and propose required directions for brachytherapy dosimetric audit in the future. The concern over accurate source strength measurement may be essentially resolved with modern equipment and calibration methods, but brachytherapy is a rapidly developing field and dosimetric audit must keep pace. PMID:24807068

  2. ROPES eye plaque brachytherapy dosimetry for two models of (103)Pd seeds.

    PubMed

    Saidi, Pooneh; Sadeghi, Mahdi; Shirazi, Alireza; Tenreiro, Claudio

    2011-06-01

    Brachytherapy dose distributions are calculated for 15 mm ROPES eye plaque loaded with model Theragenics200 and IR06-(103)Pd seeds. The effects of stainless steel backing and Acrylic insert on dose distribution along the central axis of the eye plaque and at critical ocular structure are investigated. Monte Carlo simulation was carried out with the Version 5 of the MCNP. The dose at critical ocular structure by considering the eye composition was calculated. Results are compared with the calculated data for COMS eye plaque loaded with Theragenics200 palladium-103 seeds and model 6711 iodine-125 seed. The air kerma strength of the IR06-(103)Pd seed to deliver 85 Gy in apex of tumor in water medium was calculated to be 4.10 U/seed. Along the central axis of stainless steel plaque loaded with new (103)Pd seeds in Acrylic insert, the dose reduction relative to water is 6.9% at 5 mm (apex). Removal of the Acrylic insert from the plaque (replacing with water) did not make significantly difference in dose reduction results (~0.2%). The presence of the stainless steel backing results in dose enhancement near the plaque relative to water. Doses at points of interest are higher for ROPES eye plaque when compared to COMS eye plaque. The dosimetric parameters calculated in this work for the new palladium seed, showed that in dosimetry point of view, the IR06-(103)Pd seed is suitable for use in brachytherapy. The effect of Acrylic insert on dose distribution is negligible and the main effect on dose reduction is due to the presence of stainless steel plaque backing.

  3. Establishing High-Quality Prostate Brachytherapy Using a Phantom Simulator Training Program

    SciTech Connect

    Thaker, Nikhil G.; Kudchadker, Rajat J.; Swanson, David A.; Albert, Jeffrey M.; Bruno, Teresa L.; Prestidge, Bradley R.; Crook, Juanita M.; Cox, Brett W.; Potters, Louis; Moran, Brian J.; Keyes, Mira; Kuban, Deborah A.; Frank, Steven J.

    2014-11-01

    Purpose: To design and implement a unique training program that uses a phantom-based simulator to teach the process of prostate brachytherapy (PB) quality assurance and improve the quality of education. Methods and Materials: Trainees in our simulator program were practicing radiation oncologists, radiation oncology residents, and fellows of the American Brachytherapy Society. The program emphasized 6 core areas of quality assurance: patient selection, simulation, treatment planning, implant technique, treatment evaluation, and outcome assessment. Using the Iodine 125 ({sup 125}I) preoperative treatment planning technique, trainees implanted their ultrasound phantoms with dummy seeds (ie, seeds with no activity). Pre- and postimplant dosimetric parameters were compared and correlated using regression analysis. Results: Thirty-one trainees successfully completed the simulator program during the period under study. The mean phantom prostate size, number of seeds used, and total activity were generally consistent between trainees. All trainees met the V100 >95% objective both before and after implantation. Regardless of the initial volume of the prostate phantom, trainees' ability to cover the target volume with at least 100% of the dose (V100) was not compromised (R=0.99 pre- and postimplant). However, the V150 had lower concordance (R=0.37) and may better reflect heterogeneity control of the implant process. Conclusions: Analysis of implants from this phantom-based simulator shows a high degree of consistency between trainees and uniformly high-quality implants with respect to parameters used in clinical practice. This training program provides a valuable educational opportunity that improves the quality of PB training and likely accelerates the learning curve inherent in PB. Prostate phantom implantation can be a valuable first step in the acquisition of the required skills to safely perform PB.

  4. Pilot Study Testing the Technical Feasibility and Toxicity of High Dose Rate Brachytherapy Combined with Hyperthermia to Treat Prostate Cancer Recurrences after External Beam Irradiation or Permanent Seed Implant Failure

    DTIC Science & Technology

    2004-07-01

    Jones (Duke): Uposomal chemotherapy and hyperthermia for breast cancer Coordinators: P. Corry, C. Diederich, P. Stauffer -14.00-14.25: P. Corry...infrared), and in preparation: skin and breast ( hyperthermia and ablation studies). These generic models are constructed using data of patients, anatomy... Hyperthermia to Treat Prostate Cancer Recurrences after External Beam Irradiation or Permanent Seed Implant Failure PRINCIPAL INVESTIGATOR: Peter M

  5. [Safety in brachytherapy].

    PubMed

    Marcié, S; Marinello, G; Peiffert, D; Lartigau, É

    2013-04-01

    No technique can now be used without previously considering the safety of patients, staff and public and risk management. This is the case for brachytherapy. The various aspects of brachytherapy are discussed for both the patient and the staff. For all, the risks must be minimized while achieving a treatment of quality. It is therefore necessary to establish a list as comprehensive as possible regardless of the type of brachytherapy (low, high, pulsed dose-rate). Then, their importance must be assessed with the help of their criticality. Radiation protection of personnel and public must take into account the many existing regulation texts. Four axes have been defined for the risk management for patients: organization, preparation, planning and implementation of treatment. For each axis, a review of risks is presented, as well as administrative, technical and medical dispositions for staff and the public.

  6. Robotic brachytherapy of the prostate.

    PubMed

    Wilson, Kyle J

    2009-01-01

    Recent applications of robotics in the field of prostate brachytherapy are seeding the future and could potentially lead to a fully automated prostate brachytherapy surgery. Currently, a typical prostate brachytherapy surgery involves the implantation of upwards of 100 radioactive I-125 seeds by a surgeon. This review supplies background information on prostate biology, brachytherapy of the prostate, robotic brachytherapy, and transrectal ultrasound. Subsequently, it examines the physics involved in ultrasound, radiation from an I-125 source, dosimetry, and robotics. A current semi-automated robotic brachytherapy system is examined in detail and a discussion on future improvements is outlined. Finally, future work to improve prostate brachytherapy is postulated, most notably, phantom optimization using polyvinyl alcohol cryogel. The future of robotic brachytherapy lies in the advent of more sophisticated robotics. This review will give the reader a superior understanding of brachytherapy and its recent robotic advancements. Hopefully, this review will generate new ideas needed to advance prostate brachytherapy procedures leading to more accurate dosimetry, faster procedure time, less ionizing radiation received by surgery staff, more rapid patient recovery, and an overall safer procedure.

  7. Directional interstitial brachytherapy from simulation to application

    NASA Astrophysics Data System (ADS)

    Lin, Liyong

    Organs at risk (OAR) are sometimes adjacent to or embedded in or overlap with the clinical target volume (CTV) to be treated. The purpose of this PhD study is to develop directionally low energy gamma-emitting interstitial brachytherapy sources. These sources can be applied between OAR to selectively reduce hot spots in the OARs and normal tissues. The reduction of dose over undesired regions can expand patient eligibility or reduce toxicities for the treatment by conventional interstitial brachytherapy. This study covers the development of a directional source from design optimization to construction of the first prototype source. The Monte Carlo code MCNP was used to simulate the radiation transport for the designs of directional sources. We have made a special construction kit to assemble radioactive and gold-shield components precisely into D-shaped titanium containers of the first directional source. Directional sources have a similar dose distribution as conventional sources on the treated side but greatly reduced dose on the shielded side, with a sharp dose gradient between them. A three-dimensional dose deposition kernel for the 125I directional source has been calculated. Treatment plans can use both directional and conventional 125I sources at the same source strength for low-dose-rate (LDR) implants to optimize the dose distributions. For prostate tumors, directional 125I LDR brachytherapy can potentially reduce genitourinary and gastrointestinal toxicities and improve potency preservation for low risk patients. The combination of better dose distribution of directional implants and better therapeutic ratio between tumor response and late reactions enables a novel temporary LDR treatment, as opposed to permanent or high-dose-rate (HDR) brachytherapy for the intermediate risk T2b and high risk T2c tumors. Supplemental external-beam treatments can be shortened with a better brachytherapy boost for T3 tumors. In conclusion, we have successfully finished the

  8. Longitudinal Magnetic Resonance Imaging Features of Glioblastoma Multiforme Treated With Radiotherapy With or Without Brachytherapy

    SciTech Connect

    Aiken, Ashley H. Chang, Susan M.; Larson, David; Butowski, Nicholas; Cha, Soonmee

    2008-12-01

    Purpose: To compare temporal patterns of recurrent contrast enhancement in patients with glioblastoma multiforme (GBM) treated with brachytherapy plus external beam radiotherapy (EBRT) vs. EBRT alone. Methods and Materials: We evaluated serial MRI scans for 15 patients who received brachytherapy followed by EBRT (6000 cGy) and 20 patients who received standard EBRT alone (5940-6000 cGy). Brachytherapy consisted of permanent, low-activity {sup 125}I seeds placed around the resection cavity at the time of initial gross total resection. Contrast enhancement (linear, nodular, feathery, or solid), serial progression, and location of contrast enhancement were described. Results: In the EBRT group, 14 patients demonstrated focal nodular contrast enhancement along the resection cavity within 4 months. The 6 remaining EBRT patients developed either transient linear enhancement or no abnormal enhancement. In the brachytherapy plus EBRT group, 7 patients initially developed linear rim enhancement within 4 months that progressed to feathery contrast enhancement over the course of 1 to 2 years. Histopathology confirmed radiation necrosis in all 7 patients. The remaining 8 brachytherapy patients eventually developed focal nodular contrast enhancement along the resection cavity and tumor recurrence. Conclusions: Our data suggest that longitudinal MRI features differ between GBM patients treated with EBRT vs. brachytherapy plus EBRT. In both groups, nodular enhancement adjacent to or remote from the resection cavity strongly suggested tumor recurrence. Feathery enhancement, which progressed from linear rim enhancement immediately adjacent to the cavity, seen only in brachytherapy patients, strongly indicated radiation necrosis.

  9. Radioactive seed migration following parotid gland interstitial brachytherapy.

    PubMed

    Fan, Yi; Huang, Ming-Wei; Zhao, Yi-Jiao; Gao, Hong; Zhang, Jian-Guo

    2017-09-15

    To evaluate the incidence and associated factors of pulmonary seed migration after parotid brachytherapy using a novel migrated seed detection technique. Patients diagnosed with parotid cancer who underwent permanent parotid brachytherapy from January 2006 to December 2011 were reviewed retrospectively. Head and neck CT scans and chest X-rays were evaluated during routine follow-up. Mimics software and Geomagic Studio software were used for seed reconstruction and migrated seed detection from the original implanted region, respectively. Postimplant dosimetry analysis was performed after seeds migration if the seeds were still in their emitting count. Adverse clinical sequelae from seed embolization to the lung were documented. The radioactive seed implants were identified on chest X-rays in 6 patients. The incidence rate of seed migration in 321 parotid brachytherapy patients was 1.87% (6/321) and that of individual seed migration was 0.04% (6/15218 seeds). All migrated seeds were originally from the retromandibular region. No adverse dosimetric consequences were found in the target region. Pulmonary symptoms were not reported by any patient in this study. In our patient set, migration of radioactive seeds with an initial radioactivity of 0.6-0.7 mCi to the chest following parotid brachytherapy was rare. Late migration of a single seed from the central target region did not affect the dosimetry significantly, and patients did not have severe short-term complications. This study proposed a novel technique to localize the anatomical origin of the migrated seeds during brachytherapy. Our evidence suggested that placement of seeds adjacent to blood vessels was associated with an increased likelihood of seed migration to the lungs. Copyright © 2017 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  10. Low-dose rate brachytherapy for patients with low- or intermediate-risk prostate cancer: A systematic review.

    PubMed

    Rodrigues, George; Yao, Xiaomei; Loblaw, D Andrew; Brundage, Michael; Chin, Joseph L

    2013-11-01

    We review the current evidence for the role of low-dose rate brachytherapy (PB) in patients with low- or intermediate-risk prostate cancer using a systematic review of the literature. We searched MEDLINE and EMBASE (from January 1996 to October 2011), the Cochrane Library, relevant guideline web-sites, and websites for meetings specific for genitourinary diseases. Ten systematic reviews and 55 single-study papers met the pre-planned study selection criteria. In the end, 36 articles were abstracted and analyzed for this systematic review. There is no evidence for a difference in efficacy between PB and external beam radiation therapy (EBRT), or between PB and radical prostatectomy (RP). During the 6 months to 3 years after treatment, PB was associated with less urinary incontinence and sexual impotency than RP, and RP was associated with less urinary irritation and rectal morbidity than PB. However, these differences diminished over time. PB conferred less risk of impotency and rectal morbidity in the three years after treatment than EBRT. Iodine-125 and alladium-103 did not differ with respect to biochemical relapse-free survival and patient-reported outcomes. PB alone is a treatment option with equal efficacy to EBRT or RP alone in patients with newly diagnosed low- or intermediate-risk prostate cancer who require or choose active treatment.

  11. The 1999 patterns of care study of radiotherapy in localized prostate carcinoma: a comprehensive survey of prostate brachytherapy in the United States.

    PubMed

    Lee, W Robert; Moughan, Jennifer; Owen, Jean B; Zelefsky, Michael J

    2003-11-01

    The objective of the current study was to provide descriptive information on a representative national sample of patients with prostate carcinoma who were treated with prostate brachytherapy (PB) in calendar year 1999. A random survey was conducted by the Patterns of Care Study in radiation oncology of 59 facilities (1 facility had no eligible patients) that treated patients with prostate carcinoma in 1999 in the United States. A weighted sample size of 36,496 patients with prostate cancer was included in the 1999 survey (unweighted sample size, 554 patients). The main measures were the clinical characteristics of men prior to treatment and the technical characteristics of PB. Patients were classified into three prognostic groups according to T stage, pretreatment prostate specific antigen (PSA) level, and Gleason score. A weighted sample size of 13,293 patients (36%; unweighted sample size, 162 patients) was treated with PB. Compared with a weighted sample size of 23,203 patients (64%; unweighted sample size, 392 patients) was treated with external beam radiotherapy (EB), patients who received PB were significantly younger (mean age: PB group, 67.7 years; EB group, 70.8 years; P = 0.0006). The mean pretreatment PSA level for the PB group was lower compared with the EB group (9.9 ng/mL vs. 13.33 ng/mL; P = 0.0015). The prognostic groupings were more favorable for patients in the PB group compared with patients in EB group (P = 0.0365). The utilization of androgen deprivation therapy (ADT) in the PB group was similar to the utilization of ADT in the EB group (40.4% vs. 51.3%; P = 0.2282). The vast majority of men who were treated with PB received low-dose-rate, permanent sources (89%). Fifty-four percent of men received PB monotherapy (PBM), and the remaining 46% were treated with EB in addition to PB (EBPB). The prognostic groupings were more favorable for patients in the PBM group compared with patients in the EBPB group (P = 0.0037). Of the men who were treated

  12. Brachytherapy for clinically localized prostate cancer: optimal patient selection.

    PubMed

    Kollmeier, Marisa A; Zelefsky, Michael J

    2011-10-01

    The objective of this review is to present an overview of each modality and delineate how to best select patients who are optimal candidates for these treatment approaches. Prostate brachytherapy as a curative modality for clinically localized prostate cancer has become increasingly utilized over the past decade; 25% of all early cancers are now treated this way in the United States (1). The popularity of this treatment strategy lies in the highly conformal nature of radiation dose, low morbidity, patient convenience, and high efficacy rates. Prostate brachytherapy can be delivered by either a permanent interstitial radioactive seed implantation (low dose rate [LDR]) or a temporary interstitial insertion of iridium-192 (Ir192) afterloading catheters. The objective of both of these techniques is to deliver a high dose of radiation to the prostate gland while exposing normal surrounding tissues to minimal radiation dose. Brachytherapy techniques are ideal to achieve this goal given the close proximity of the radiation source to tumor and sharp fall off of the radiation dose cloud proximate to the source. Brachytherapy provides a powerful means of delivering dose escalation above and beyond that achievable with intensity-modulated external beam radiotherapy alone. Careful selection of appropriate patients for these therapies, however, is critical for optimizing both disease-related outcomes and treatment-related toxicity.

  13. A novel ytterbium-169 brachytherapy source and delivery system for use in conjunction with minimally invasive wedge resection of early-stage lung cancer

    PubMed Central

    Leonard, Kara Lynne; DiPetrillo, Thomas A.; Munro, John J.; Wazer, David E.

    2011-01-01

    PURPOSE To describe a novel source–delivery system for intraoperative brachytherapy in patients with early-stage lung cancer that is readily adaptable to a video-assisted thoracoscopic surgery approach and can be precisely delivered to achieve optimal dose distribution. METHODS AND MATERIALS Radioactive ytterbium-169 (169Yb) was sealed within a titanium tube 0.28 mm in diameter and then capped and resealed by titanium wires laser welded to the tube to serve as the legs of a tissue-fastening system. Dose simulations were performed using Monte Carlo computer code (Los Alamos National Laboratory, Los Alamos, NM) to mimic the geometric and elemental compositions of the source, fastening apparatus, and surroundings. RESULTS Five test source capsules were subjected to a tensile load to failure. Failure in each capsule occurred in the wire of the fastener leg; there were no weld failures. Monte Carlo simulations and subsequent dose measurement showed the perturbation by the source legs in the deployed (bent over) position to be small (4–5%) for 169Yb and much less than that for iodine-125 (32%). CONCLUSION We have developed a 169Yb brachytherapy source–delivery system that can be used in conjunction with commercially available surgical stapling instruments, facilitates the precise placement of brachytherapy sources relative to the surgical margin, assures the seeds remain fixed in their precise position for the duration of the treatment, overcomes the technical difficulties of manipulating the seeds through the narrow surgical incision associated with video-assisted thoracoscopic surgery, and reduces the radiation dose to the clinicians. PMID:20705525

  14. Comparative cost-effectiveness of focal and total salvage 125I brachytherapy for recurrent prostate cancer after primary radiotherapy

    PubMed Central

    Piena, Marjanne A.; Steuten, Lotte M.G.; van der Voort van Zyp, Jochem R.N.; Moerland, Marinus A.; van Vulpen, Marco

    2016-01-01

    Purpose Focal salvage (FS) iodine 125 (125I) brachytherapy could be an effective treatment for locally radiorecurrent prostate cancer (PCa). Toxicity is often reduced compared to total salvage (TS) while cancer control can be maintained, which could increase cost-effectiveness. The current study estimates the incremental cost per quality-adjusted life year (QALY) of FS compared to TS. Material and methods A decision analytic Markov model was developed, which compares costs and QALYs associated with FS and TS. A 3-year time horizon was adopted with six month cycles, with a hospital perspective on costs. Probabilities for genitourinary (GU) and gastrointestinal (GI) toxicity and their impact on health-related quality of life (SF-36) were derived from clinical studies in the University Medical Center Utrecht (UMCU). Probabilistic sensitivity analysis, using 10,000 Monte Carlo simulations, was performed to quantify the joint decision uncertainty up to the recommended maximum willingness-to-pay threshold of €80,000/QALY. Results Focal salvage dominates TS as it results in less severe toxicity and lower treatment costs. Decision uncertainty is small, with a 97-100% probability for FS to be cost-effective compared to TS (€0-€80,000/QALY). Half of the difference in costs between FS and TS was explained by higher treatment costs of TS, the other half by higher incidence of severe toxicity. One-way sensitivity analyses show that model outcomes are most sensitive to utilities and probabilities for severe toxicity. Conclusions Focal salvage 125I brachytherapy dominates TS, as it has lower treatment costs and leads to less toxicity in our center. Larger comparative studies with longer follow-up are necessary to assess the exact influence on (biochemical disease free) survival and toxicity. PMID:28115953

  15. Dosimetric and technical aspects of intraoperative I-125 brachytherapy for stage I non-small cell lung cancer

    NASA Astrophysics Data System (ADS)

    Johnson, Mark; Colonias, Athanasios; Parda, David; Trombetta, Mark; Gayou, Olivier; Reitz, Bodo; Miften, Moyed

    2007-03-01

    Initial treatment outcome data from our institution for stage I non-small cell lung cancer (NSCLC) patients have shown that sublobar resection in combination with iodine-125 (I-125) brachytherapy is associated with recurrence rates of 2.0%, compared to 18.6% with sublobar resection alone. In this work, the technical and dosimetric aspects required to execute this procedure from the radiation oncology perspective as well as an analysis of the dose distributions of patients treated with this technique are presented. In this treatment technique, I-125 seeds in vicryl suture are embedded into vicryl mesh and surgically inserted providing a 2.0 cm margin on each side of the resection staple line. A nomogram is developed to determine the suture spacing in the vicryl mesh, as a function of seed activity in order to deliver 120 Gy at a distance of 0.5 cm above and below the seed array. Post-operative dosimetry consists of a CT-based planning and dose volume analysis. Dose distributions, dose volume histograms and mean dose data for lung are analysed in a group of patients. Dosimetric results show significant lung sparing with only a small volume of lung irradiated for all patients with mean lung dose values ranging from 1.5 Gy to 5.4 Gy. Lung brachytherapy with I-125 at the time of sublobar resection is a highly conformal option of dose delivery for stage I NSCLC patients with compromised physiologic reserve. Patient-related toxicity clinically measured by loss of pulmonary function and radiation-induced pneumonitis have not been linked to this procedure.

  16. Sexual Function and the Use of Medical Devices or Drugs to Optimize Potency After Prostate Brachytherapy

    SciTech Connect

    Whaley, J. Taylor; Levy, Lawrence B.; Swanson, David A.; Pugh, Thomas J.; Kudchadker, Rajat J.; Bruno, Teresa L.; Frank, Steven J.

    2012-04-01

    Purpose: Prospective evaluation of sexual outcomes after prostate brachytherapy with iodine-125 seeds as monotherapy at a tertiary cancer care center. Methods and Materials: Subjects were 129 men with prostate cancer with I-125 seed implants (prescribed dose, 145 Gy) without supplemental hormonal or external beam radiation therapy. Sexual function, potency, and bother were prospectively assessed at baseline and at 1, 4, 8, and 12 months using validated quality-of-life self-assessment surveys. Postimplant dosimetry values, including dose to 10% of the penile bulb (D10), D20, D33, D50, D75, D90, and penile volume receiving 100% of the prescribed dose (V100) were calculated. Results: At baseline, 56% of patients recorded having optimal erections; at 1 year, 62% of patients with baseline erectile function maintained optimal potency, 58% of whom with medically prescribed sexual aids or drugs. Variables associated with pretreatment-to-posttreatment decline in potency were time after implant (p = 0.04) and age (p = 0.01). Decline in urinary function may have been related to decline in potency. At 1 year, 69% of potent patients younger than 70 years maintained optimal potency, whereas 31% of patients older than 70 maintained optimal potency (p = 0.02). Diabetes was related to a decline in potency (p = 0.05), but neither smoking nor hypertension were. For patients with optimal potency at baseline, mean sexual bother scores had declined significantly at 1 year (p < 0.01). Sexual potency, sexual function, and sexual bother scores failed to correlate with any dosimetric variable tested. Conclusions: Erections firm enough for intercourse can be achieved at 1 year after treatment, but most men will require medical aids to optimize potency. Although younger men were better able to maintain erections firm enough for intercourse than older men, there was no correlation between potency, sexual function, or sexual bother and penile bulb dosimetry.

  17. Seed migration to the spinal canal after postresection brachytherapy to treat a large brain metastasis.

    PubMed

    Hirschfeld, Cole B; Schwartz, Theodore H; Parashar, Bhupesh; Wernicke, A Gabriella

    2016-01-01

    Seed migration after interstitial prostate brachytherapy has been well documented in the literature. However, there have been no detailed reports of seed migration after permanent interstitial brachytherapy to treat cerebral malignancies. In this article, the authors report a rare case of seed migration after adjuvant cesium-131 ((131)Cs) brachytherapy was used to treat a large paraventricular brain metastasis. The patient was a 63-year-old man with a 5.8-cm right frontal metastasis abutting the right lateral ventricle and causing severe edema and mass effect. The patient was enrolled in an ongoing clinical trial at our institution to receive permanent intraoperative (131)Cs brachytherapy in an effort to prevent tumor recurrence in the resection cavity. Stranded seeds were covered with Surgicel, and the cavity was filled with Tisseel to prevent seed migration. Imaging obtained at 54 days postsurgery showed no seed migration, but imaging obtained at 158 days revealed 12 brachytherapy seeds in the spinal canal from T11 to S2. The seeds were left in place because they were inactive at this time due to the short half-life of (131)Cs (9.7 days); they remained stable on followup imaging, and the patient was asymptomatic. Although the clinical consequences remain unclear, the migration of inactive seeds is not currently considered to be a complication of intracerebral brachytherapy and we do not believe that additional measures must be taken to prevent it. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  18. Low-dose-rate or high-dose-rate brachytherapy in treatment of prostate cancer – between options

    PubMed Central

    2013-01-01

    Purpose Permanent low-dose-rate (LDR-BT) and temporary high-dose-rate (HDR-BT) brachytherapy are competitive techniques for clinically localized prostate radiotherapy. Although a randomized trial will likely never to be conducted comparing these two forms of brachytherapy, a comparative analysis proves useful in understanding some of their intrinsic differences, several of which could be exploited to improve outcomes. The aim of this paper is to look for possible similarities and differences between both brachytherapy modalities. Indications and contraindications for monotherapy and for brachytherapy as a boost to external beam radiation therapy (EBRT) are presented. It is suggested that each of these techniques has attributes that advocates for one or the other. First, they represent the extreme ends of the spectrum with respect to dose rate and fractionation, and therefore have inherently different radiobiological properties. Low-dose-rate brachytherapy has the great advantage of being practically a one-time procedure, and enjoys a long-term follow-up database supporting its excellent outcomes and low morbidity. Low-dose-rate brachytherapy has been a gold standard for prostate brachytherapy in low risk patients since many years. On the other hand, HDR is a fairly invasive procedure requiring several sessions associated with a brief hospital stay. Although lacking in significant long-term data, it possesses the technical advantage of control over its postimplant dosimetry (by modulating the source dwell time and position), which is absent in LDR brachytherapy. This important difference in dosimetric control allows HDR doses to be escalated safely, a flexibility that does not exist for LDR brachytherapy. Conclusions Radiobiological models support the current clinical evidence for equivalent outcomes in localized prostate cancer with either LDR or HDR brachytherapy, using current dose regimens. At present, all available clinical data regarding these two techniques

  19. Effect of implanted brachytherapy seeds on optical fluence distribution: preliminary ex vivo study

    NASA Astrophysics Data System (ADS)

    Hetzel, Fred W.; Chen, Qun; Ding, Meisong; Newman, Francis; Dole, Kenneth C.; Huang, Zheng; Blanc, Dominique

    2007-02-01

    Photodynamic therapy (PDT) has gradually found its place in the treatment of malignant and non-malignant human diseases. Currently, interstitial PDT is being explored as an alternative modality for newly diagnosed and recurrent organ-confined prostate cancer. The interstitial PDT for the treatment of prostate cancer might be considered to treat prostates with permanent radioactive seeds implantation. However, the effect of implanted brachytherapy seeds on the optical fluence distribution of PDT light has not been studied before. This study investigated, for the first time, the effect of brachytherapy seed on the optical fluence distribution of 760 nm light in ex vivo models (meat and canine prostate).

  20. Intraoral angiosarcoma: treatment with a brachytherapy prosthesis.

    PubMed

    Rosen, Evan B; Ko, Eugene; Wolden, Suzanne; Huryn, Joseph M; Estilo, Cherry L

    2015-03-01

    Angiosarcomas are rare, malignant neoplasms of vascular origin that account for less than 1% of all soft tissue tumors. Angiosarcomas of the oral cavity are especially rare, and brachytherapy may be prescribed as a localized treatment to manage these malignancies. Intraoral brachytherapy requires collaboration between the radiation oncologist and a dental professional for the fabrication of the brachytherapy delivery prosthesis. This clinical report describes an intraoral angiosarcoma and the fabrication of an intraoral brachytherapy prosthesis to manage this malignancy.

  1. Magnetic resonance image guided brachytherapy.

    PubMed

    Tanderup, Kari; Viswanathan, Akila N; Kirisits, Christian; Frank, Steven J

    2014-07-01

    The application of magnetic resonance image (MRI)-guided brachytherapy has demonstrated significant growth during the past 2 decades. Clinical improvements in cervix cancer outcomes have been linked to the application of repeated MRI for identification of residual tumor volumes during radiotherapy. This has changed clinical practice in the direction of individualized dose administration, and resulted in mounting evidence of improved clinical outcome regarding local control, overall survival as well as morbidity. MRI-guided prostate high-dose-rate and low-dose-rate brachytherapies have improved the accuracy of target and organs-at-risk delineation, and the potential exists for improved dose prescription and reporting for the prostate gland and organs at risk. Furthermore, MRI-guided prostate brachytherapy has significant potential to identify prostate subvolumes and dominant lesions to allow for dose administration reflecting the differential risk of recurrence. MRI-guided brachytherapy involves advanced imaging, target concepts, and dose planning. The key issue for safe dissemination and implementation of high-quality MRI-guided brachytherapy is establishment of qualified multidisciplinary teams and strategies for training and education.

  2. Anisotropy characterization of I-125 seed with attached encapsulated cobalt chloride complex contrast agent markers for MRI-based prostate brachytherapy.

    PubMed

    Frank, Steven J; Tailor, Ramesh C; Kudchadker, Rajat J; Martirosyan, Karen S; Stafford, R Jason; Elliott, Andrew M; Swanson, David A; Sing, David; Choi, Jonathan; Mourtada, Firas; Ibbott, Geoffrey S

    2011-01-01

    We have developed a novel MRI marker for prostate brachytherapy. The purpose of this study was to evaluate the changes in anisotropy when cobalt chloride complex contrast agent encapsulated contrast agent markers (C4-ECAM) were placed adjacent to an iodine-125 (I-125) titanium seed, and to verify that the C4-ECAMs were visible on magnetic resonance imaging (MRI) after radiation exposure. Two C4-ECAMs were verified to be MRI visible in a phantom before radiation exposure. The C4-ECAMs were then attached to each end of a 12.7-U (10-mCi) I-125 titanium seed in a polymer tube. Anisotropy was measured and analyzed with the seed alone and with attached C4-ECAMs by suspending thermoluminescent dosimeters in a water phantom in 2 circles surrounding the radioactive source with radius of 1 or 2 cm. A T1-weighted MRI evaluation of C4-ECAMs was then performed after exposure to the amount of radiation typically delivered during 1 month of prostate brachytherapy. Measured values of the anisotropy function F(r, θ) for the I-125 seed with and without the C4-ECAMs were mutually statistically indistinguishable (standard error of the mean <4.2%) and agreed well with published TG-43 values for the bare seed. As expected, the anisotropy function ϕ(an)(r) for the 2 datasets (with and without C4-ECAMs) derived from the measured F(r, θ) did not exhibit statistically measurable difference. Both datasets showed agreement with the published TG-43 ϕ(an)(r) for the bare seed. The C4-ECAMs were well visualized by MRI after 1 month of radiation exposure. There were no changes in anisotropy when the C4-ECAMs were placed next to an I-125 radioactive seed, and the C4-ECAMs were visualized after radiation exposure.

  3. Anisotropy Characterization of I-125 Seed with Attached Encapsulated Cobalt Chloride Complex Contrast Agent Markers for MRI-Based Prostate Brachytherapy

    SciTech Connect

    Frank, Steven J.; Tailor, Ramesh C.; Kudchadker, Rajat J.; Martirosyan, Karen S.; Stafford, R. Jason; Elliott, Andrew M.; Swanson, David A.; Sing, David; Choi, Jonathan; Mourtada, Firas; Ibbott, Geoffrey S.

    2011-07-01

    We have developed a novel MRI marker for prostate brachytherapy. The purpose of this study was to evaluate the changes in anisotropy when cobalt chloride complex contrast agent encapsulated contrast agent markers (C4-ECAM) were placed adjacent to an iodine-125 (I-125) titanium seed, and to verify that the C4-ECAMs were visible on magnetic resonance imaging (MRI) after radiation exposure. Two C4-ECAMs were verified to be MRI visible in a phantom before radiation exposure. The C4-ECAMs were then attached to each end of a 12.7-U (10-mCi) I-125 titanium seed in a polymer tube. Anisotropy was measured and analyzed with the seed alone and with attached C4-ECAMs by suspending thermoluminescent dosimeters in a water phantom in 2 circles surrounding the radioactive source with radius of 1 or 2 cm. A T1-weighted MRI evaluation of C4-ECAMs was then performed after exposure to the amount of radiation typically delivered during 1 month of prostate brachytherapy. Measured values of the anisotropy function F(r, {theta}) for the I-125 seed with and without the C4-ECAMs were mutually statistically indistinguishable (standard error of the mean <4.2%) and agreed well with published TG-43 values for the bare seed. As expected, the anisotropy function {phi}{sub an}(r) for the 2 datasets (with and without C4-ECAMs) derived from the measured F(r, {theta}) did not exhibit statistically measurable difference. Both datasets showed agreement with the published TG-43 {phi}{sub an}(r) for the bare seed. The C4-ECAMs were well visualized by MRI after 1 month of radiation exposure. There were no changes in anisotropy when the C4-ECAMs were placed next to an I-125 radioactive seed, and the C4-ECAMs were visualized after radiation exposure.

  4. SU-F-I-19: MRI Positive Contrast Visualization of Prostate Brachytherapy Seeds Using An Integrated Laplacian-Based Phase Processing

    SciTech Connect

    Soliman, A; Safigholi, H; Nosrati, R; Owrangi, A; Morton, G; Song, W

    2016-06-15

    Purpose: To propose a new method that provides a positive contrast visualization of the prostate brachytherapy seeds using the phase information from MR images. Additionally, the feasibility of using the processed phase information to distinguish seeds from calcifications is explored. Methods: A gel phantom was constructed using 2% agar dissolved in 1 L of distilled water. Contrast agents were added to adjust the relaxation times. Four iodine-125 (Eckert & Ziegler SML86999) dummy seeds were placed at different orientations with respect to the main magnetic field (B0). Calcifications were obtained from a sheep femur cortical bone due to its close similarity to human bone tissue composition. Five samples of calcifications were shaped into different dimensions with lengths ranging between 1.2 – 6.1 mm.MR imaging was performed on a 3T Philips Achieva using an 8-channel head coil. Eight images were acquired at eight echo-times using a multi-gradient echo sequence. Spatial resolution was 0.7 × 0.7 × 2 mm, TR/TE/dTE = 20.0/2.3/2.3 ms and BW = 541 Hz/pixel. Complex images were acquired and fed into a two-step processing pipeline: the first includes phase unwrapping and background phase removal using Laplacian operator (Wei et al. 2013). The second step applies a specific phase mask on the resulting tissue phase from the first step to provide the desired positive contrast of the seeds and to, potentially, differentiate them from the calcifications. Results: The phase-processing was performed in less than 30 seconds. The proposed method has successfully resulted in a positive contrast of the brachytherapy seeds. Additionally, the final processed phase image showed difference between the appearance of seeds and calcifications. However, the shape of the seeds was slightly distorted compared to the original dimensions. Conclusion: It is feasible to provide a positive contrast of the seeds from MR images using Laplacian operator-based phase processing.

  5. Prostate cancer brachytherapy: guidelines overview.

    PubMed

    Wojcieszek, Piotr; Białas, Brygida

    2012-06-01

    Prostate cancer, due to wide availability of PSA tests, is very often diagnosed in early stage, nowadays. This makes management of this disease even harder in every day oncology care. There is a wide range of treatment options including surgery, radiotherapy and active surveillance, but essential question is which treatment patient and oncologist should decide for. Due to recent publication of Prostate Cancer Results Study Group, in which brachytherapy is one of supreme curative options for prostate cancer, we decided to overview most present european and north american recommendations. National Comprehensive Cancer Network, American Society for Radiation Oncology, American Brachytherapy Society, European Association of Urology and Groupe Européen de Curiethérapie of European Society for Therapeutic Radiation Oncology guidelines are overviewed, particularly focusing on HDR and LDR brachytherapy.

  6. Prostate cancer brachytherapy: guidelines overview

    PubMed Central

    Białas, Brygida

    2012-01-01

    Prostate cancer, due to wide availability of PSA tests, is very often diagnosed in early stage, nowadays. This makes management of this disease even harder in every day oncology care. There is a wide range of treatment options including surgery, radiotherapy and active surveillance, but essential question is which treatment patient and oncologist should decide for. Due to recent publication of Prostate Cancer Results Study Group, in which brachytherapy is one of supreme curative options for prostate cancer, we decided to overview most present european and north american recommendations. National Comprehensive Cancer Network, American Society for Radiation Oncology, American Brachytherapy Society, European Association of Urology and Groupe Européen de Curiethérapie of European Society for Therapeutic Radiation Oncology guidelines are overviewed, particularly focusing on HDR and LDR brachytherapy. PMID:23349655

  7. Evaluation of the MIM Symphony treatment planning system for low-dose-rate- prostate brachytherapy.

    PubMed

    Dhanesar, Sandeep K; Lim, Tze Y; Du, Weiliang; Bruno, Teresa L; Frank, Steven J; Kudchadker, Rajat J

    2015-09-08

    MIM Symphony is a recently introduced low-dose-rate prostate brachytherapy treatment planning system (TPS). We evaluated the dosimetric and planning accuracy of this new TPS compared to the universally used VariSeed TPS. For dosimetric evaluation of the MIM Symphony version 5.4 TPS, we compared dose calculations from the MIM Symphony TPS with the formalism recommended by the American Association of Physicists in Medicine Task Group 43 report (TG-43) and those generated by the VariSeed version 8.0 TPS for iodine-125 (I-125; Models 6711 and IAI-125A), palladium-103 (Pd-103; Model 200), and cesium-131 (Cs-131; Model Cs-1). Validation was performed for both line source and point source approximations. As part of the treatment planning validation, first a QA phantom (CIRS Brachytherapy QA Phantom Model 045 SN#D7210-3) containing three ellipsoid objects with certified volumes was scanned in order to check the volume accuracy of the contoured structures in MIM Symphony. Then the DICOM data containing 100 patient plans from the VariSeed TPS were imported into the MIM Symphony TPS. The 100 plans included 25 each of I-125 pre-implant plans, Pd-103 pre-implant plans, I-125 Day 30 plans (i.e., from 1 month after implantation), and Pd-103 Day 30 plans. The dosimetric parameters (including prostate volume, prostate D90 values, and rectum V100 values) of the 100 plans were calculated independently on the two TPSs. Other TPS tests that were done included verification of source input and geometrical accuracy, data transfer between different planning systems, text printout, 2D dose plots, DVH printout, and template grid accuracy. According to the line source formalism, the dosimetric results between the MIM Symphony TPS and TG-43 were within 0.5% (0.02 Gy) for r > 1 cm. In the line source approximation validation, MIM Symphony TPS values agreed with VariSeed TPS values to within 0.5% (0.09 Gy) for r > 1 cm. Similarly, in point source approximation validation, the MIM Symphony values

  8. Brachytherapy volume visualization

    NASA Astrophysics Data System (ADS)

    Persons, Timothy M.; Webber, Richard L.; Hemler, Paul F.; Bettermann, Wolfram; Bourland, J. Daniel

    2000-04-01

    Conventional localization schemes for brachytherapy seed implants using biplane or stereoscopic projection radio- graphs can suffer form scaling distortions and poor visibility of implanted seeds, resulting in compromised source tracking and dosimetric inaccuracies. This paper proposes an alternative method for improving the visualization and thus, localization, of radiotherapy implants by synthesizing, form as few as two radiographic projections, a 3D image free of divergence artifacts. The result produces more accurate seed localization leading to improved dosimetric accuracy. Two alternative approaches are compared. The first uses orthogonal merging. The second employs the technique of tuned-aperture computed tomography (TACT), whereby 3D reconstruction is performed by shifting and adding of well-sampled projections relative to a fiducial reference system. Phantom results using nonlinear visualization methods demonstrate the applicability of localizing individual seeds for both approaches. Geometric errors are eliminated by a calibration scheme derived from the fiducial pattern that is imaged concurrently with the subject. Both merging and TACT approaches enhance seed localization by improving visualization of the seed distribution over biplanar radiographs. Unlike current methods, both alternatives demonstrate continuos one-to-one source tracking in 3D, although elimination of scaling artifacts requires more than two projections when using the merging method.

  9. Brachytherapy dosimeter with silicon photomultipliers

    NASA Astrophysics Data System (ADS)

    Moutinho, L. M.; Castro, I. F. C.; Peralta, L.; Abreu, M. C.; Veloso, J. F. C. A.

    2015-07-01

    In-vivo and in-situ measurement of the radiation dose administered during brachytherapy faces several technical challenges, requiring a very compact, tissue-equivalent, linear and highly sensitive dosimeter, particularly in low-dose rate brachytherapy procedures, which use radioactive seeds with low energy and low dose deposition rate. In this work we present a scintillating optical fiber dosimeter composed of a flexible sensitive probe and a dedicated electronic readout system based on silicon photomultiplier photodetection, capable of operating both in pulse and current modes. The performance of the scintillating fiber optic dosimeter was evaluated in low energy regimes, using an X-ray tube operating at voltages of 40-50 kV and currents below 1 mA, to assess minimum dose response of the scintillating fiber. The dosimeter shows a linear response with dose and is capable of detecting mGy dose variations like an ionization chamber. Besides fulfilling all the requirements for a dosimeter in brachytherapy, the high sensitivity of this device makes it a suitable candidate for application in low-dose rate brachytherapy. According to Peralta and Rego [1], the BCF-10 and BCF-60 scintillating optical fibers used in dosimetry exhibit high variations in their sensitivity for photon beams in the 25-100 kVp energy range. Energy linearity for energies below 50 keV needs to be further investigated, using monochromatic X-ray photons.

  10. Iodine-125 metaraminol: A new platelet specific labeling agent

    SciTech Connect

    Ohmomo, Y.; Yokoyama, A.; Kawaii, K.; Horiuchi, K.; Saji, H.; Torizuka, K.

    1984-01-01

    In the search for a platelet specific labeling agent, Metaraminol (MA), which is a sympatomimetic amine used for the treatment of hypotension, cardiogenic shock and well recognized as a drug actively incorporated and accumulated in platelet, attracted the authors' attention. Using the classical chloramine-T iodination method, a high labeling efficiency near 98%, reaching a specific activity up to about 1000 Ci/mmole was obtained. Upon the harvest of platelet, only as platelet rich plasma (PRP), the labeling with this radiopharmaceutical was easily performed by incubation at 37/sup 0/C for 10 min. Labeling efficiency as high as 63.0 +- 3.1% at 24 x 10/sup 8/ cells/ml was obtained. In in-vitro studies, the unaltered state of I-125 MA labeled platelet, with their cellular functions fully retained was demonstrated. Pharmacological study indicated a specific incorporation of I-125 MA by active transport system similar to that of 5-HT, along with passive diffusion. Then the in-vivo study carried out in rabbits with induced thrombi on the femoral artery, showed rather rapid disappearance of the I-125 MA labeled autologous platelet radioactivity, from circulating blood reaching as high thrombus-to-blood activity ratio as 19.8+-4.3 within 30 min post-administration. This new platelet labeling agent, I-125 MA, has many advantages over the use of IN-111 oxine and holds considerable promise for thrombus imaging with single photon emission CT upon the availability of I-123 MA.

  11. Image-based brachytherapy for cervical cancer

    PubMed Central

    Vargo, John A; Beriwal, Sushil

    2014-01-01

    Cervical cancer is the third most common cancer in women worldwide; definitive radiation therapy and concurrent chemotherapy is the accepted standard of care for patients with node positive or locally advanced tumors > 4 cm. Brachytherapy is an important part of definitive radiotherapy shown to improve overall survival. While results for two-dimensional X-ray based brachytherapy have been good in terms of local control especially for early stage disease, unexplained toxicities and treatment failures remain. Improvements in brachytherapy planning have more recently paved the way for three-dimensional image-based brachytherapy with volumetric optimization which increases tumor control, reduces toxicity, and helps predict outcomes. Advantages of image-based brachytherapy include: improved tumor coverage (especially for large volume disease), decreased dose to critical organs (especially for small cervix), confirmation of applicator placement, and accounting for sigmoid colon dose. A number of modalities for image-based brachytherapy have emerged including: magnetic resonance imaging (MRI), computed tomography (CT), CT-MRI hybrid, and ultrasound with respective benefits and outcomes data. For practical application of image-based brachytherapy the Groupe Europeen de Curietherapie-European Society for Therapeutic Radiology and Oncology Working Group and American Brachytherapy Society working group guideline serve as invaluable tools, additionally here-in we outline our institutional clinical integration of these guidelines. While the body of literature supporting image-based brachytherapy continues to evolve a number of uncertainties and challenges remain including: applicator reconstruction, increasing resource/cost demands, mobile four-dimensional targets and organs-at-risk, and accurate contouring of “grey zones” to avoid marginal miss. Ongoing studies, including the prospective EMBRACE (an international study of MRI-guided brachytherapy in locally advanced

  12. Image-based brachytherapy for cervical cancer.

    PubMed

    Vargo, John A; Beriwal, Sushil

    2014-12-10

    Cervical cancer is the third most common cancer in women worldwide; definitive radiation therapy and concurrent chemotherapy is the accepted standard of care for patients with node positive or locally advanced tumors > 4 cm. Brachytherapy is an important part of definitive radiotherapy shown to improve overall survival. While results for two-dimensional X-ray based brachytherapy have been good in terms of local control especially for early stage disease, unexplained toxicities and treatment failures remain. Improvements in brachytherapy planning have more recently paved the way for three-dimensional image-based brachytherapy with volumetric optimization which increases tumor control, reduces toxicity, and helps predict outcomes. Advantages of image-based brachytherapy include: improved tumor coverage (especially for large volume disease), decreased dose to critical organs (especially for small cervix), confirmation of applicator placement, and accounting for sigmoid colon dose. A number of modalities for image-based brachytherapy have emerged including: magnetic resonance imaging (MRI), computed tomography (CT), CT-MRI hybrid, and ultrasound with respective benefits and outcomes data. For practical application of image-based brachytherapy the Groupe Europeen de Curietherapie-European Society for Therapeutic Radiology and Oncology Working Group and American Brachytherapy Society working group guideline serve as invaluable tools, additionally here-in we outline our institutional clinical integration of these guidelines. While the body of literature supporting image-based brachytherapy continues to evolve a number of uncertainties and challenges remain including: applicator reconstruction, increasing resource/cost demands, mobile four-dimensional targets and organs-at-risk, and accurate contouring of "grey zones" to avoid marginal miss. Ongoing studies, including the prospective EMBRACE (an international study of MRI-guided brachytherapy in locally advanced cervical

  13. The American Brachytherapy Society recommendations for brachytherapy of uveal melanomas.

    PubMed

    Nag, Subir; Quivey, Jeanne M; Earle, John D; Followill, David; Fontanesi, James; Finger, Paul T

    2003-06-01

    This article presents the American Brachytherapy Society (ABS) guidelines for the use of brachytherapy for patients with choroidal melanomas. Members of the ABS with expertise in choroidal melanoma formulated brachytherapy guidelines based upon their clinical experience and a review of the literature. The Board of Directors of the ABS approved the final report. Episcleral plaque brachytherapy is a complex procedure and should only be undertaken in specialized medical centers with expertise in this sophisticated treatment program. Recommendations were made for patient selection, techniques, dose rates, and dosages. Most patients with very small uveal melanomas (<2.5 mm height and <10 mm in largest basal dimension) should be observed for tumor growth before treatment. Patients with a clinical diagnosis of medium-sized choroidal melanoma (between 2.5 and 10 mm in height and <16 mm basal diameter) are candidates for episcleral plaques if the patient is otherwise healthy and without metastatic disease. A histopathologic verification is not required. Small melanomas may be candidates if there is documented growth; some patients with large melanomas (>10 mm height or >16 mm basal diameter) may also be candidates. Patients with large tumors or with tumors at peripapillary and macular locations have a poorer visual outcome and lower local control that must be taken into account in the patient decision-making process. Patients with gross extrascleral extension, ring melanoma, and tumor involvement of more than half of the ciliary body are not suitable for plaque therapy. For plaque fabrication, the ophthalmologist must provide the tumor size (including basal diameters and tumor height) and a detailed fundus diagram. The ABS recommends a minimum tumor (125)I dose of 85 Gy at a dose rate of 0.60-1.05 Gy/h using AAPM TG-43 formalism for the calculation of dose. NRC or state licensing guidelines regarding procedures for handling of radioisotopes must be followed. Brachytherapy

  14. Skin dose in breast brachytherapy: Defining a robust metric.

    PubMed

    Hilts, Michelle; Halperin, Heather; Morton, Dan; Batchelar, Deidre; Bachand, Francois; Chowdhury, Rezwan; Crook, Juanita

    2015-01-01

    To define a simple, robust, and relevant metric for measuring skin dose in breast brachytherapy. Postoperative treatment plans (Day 0) for 15 permanent breast seed implant (PBSI) and 10 multicatheter high-dose-rate (MC-HDR) brachytherapy patients were included. Retrospectively, three skin structures were contoured: 2 mm external from the body; and subsurface layers 2 mm and 4 mm thick. Maximum point dose (Dmax), doses to small volumes (e.g., D0.2cc), and the volumes receiving a percentage of the prescription dose (V%, e.g., V66) were calculated. D0.2cc was investigated as a surrogate to the dose given to 1 cm(2) of skin (D1cm(2)). Pearson product-moment correlation (R(2)) was computed between metrics. Observed trends were consistent across brachytherapy technique. V% did not correlate well with any other metrics: median (range) R(2), 0.63 (0.43, 0.77) and 0.69 (0.3, 0.89) for PBSI and MC-HDR, respectively. Dmax was inconsistently correlated across contours and not well correlated with doses to small volumes: median (range) R(2), 0.85 (0.76, 0.93) and 0.88 (0.83, 0.93) for PBSI and MC-HDR, respectively. In contrast, doses to small volumes were consistently well correlated, even across skin layers: D0.1cc vs. D0.2cc median (range) R(2), 0.98 (0.97, 0.99) and 0.97 (0.94, 0.99) for PBSI and MC-HDR, respectively. Doses to small volumes are robust measures of breast skin dose and given skin's strong area effect, D0.2cc for a 2 mm thick skin layer, a simple surrogate of D1cm(2), is recommended for recording skin dose in any breast brachytherapy. Dmax is not robust and should be avoided. Copyright © 2015 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  15. TU-AB-201-10: Novel Conformal Skin Brachytherapy Device

    SciTech Connect

    Ferreira, C; Johnson, D; Ahmad, S; Rasmussen, K; Jung, J

    2015-06-15

    Purpose: A novel conformal skin brachytherapy (CSBT) device was developed to provide patient specific treatment for small inoperable lesions and irregular surfaces that are not good candidates for electron external beam, e.g. eyelids, nose, lips, ears, etc. Methods: A prototype was built and tested using radioactive seeds spaced by 1.5 mm attached to a 3D printed template. Seeds were allowed to move independently at treatment surface to conform to target geometry. Beta-emitter Praseodymium-142 (half-life: 19.12 h, average beta energy: 809 keV) and Iodine-125 Model 6711 (half-life: 59.4 days, average gamma energy: 28 keV) seeds were used to test the feasibility of the device in solid water phantom for different prescription depths and surface areas. Percent depth doses and dose profiles were analyzed. MCNPX2.6 Monte Carlo Simulation and Gafchromic EBT3 film measurements were performed for a single Pr-142 seed. Treatment with nineteen I-125 seeds was planned in BrachyVision and measured experimentally for a total dose of 500 cGy at 5.0 mm depth. Results: For a single Pr-142 seed, dose was 500.0 cGy at surface and 17.4 cGy at 5.00 mm. BrachyVision planned and film doses for I-125 seed matrix were 500 cGy and 473.5 cGy at 5 mm depth and 171.0 cGy and 201.0 cGy at 10 mm depth. Total covered surface area for Pr-142 and I-125 were 2.35 mm{sup 2} and 88.24 mm{sup 2} respectively. Profile dose fall-off showed to be very conformal to contact area with 50% of the total surface dose from a single Pr-142 and array of I-125 seeds being deposited at 0.72 mm and 0.65 mm respectively from the central axis. Conclusion: CSBT device provides a high conformal dose to small surfaces. BrachyVision can be used to predict clinical dose distributions for multiple seeds matrix. Different radioactive seeds can be used to suit prescription depth and treatment area.

  16. Prostate Brachytherapy With Oblique Needles to Treat Large Glands and Overcome Pubic Arch Interference

    SciTech Connect

    Ryu, Bon; Bax, Jeff; Edirisinge, Chandima; Lewis, Craig; Chen, Jeff; D'Souza, David; Fenster, Aaron; Wong, Eugene

    2012-08-01

    Purpose: First, to show that low-dose-rate prostate brachytherapy plans using oblique needle trajectories are more successful than parallel trajectories for large prostates with pubic arch interference (PAI); second, to test the accuracy of delivering an oblique plan by using a three-dimensional (3D) transrectal ultrasonography (TRUS)-guided mechatronic system. Methods and Materials: Prostates were contoured for 5 subjects' 3D TRUS images showing a maximum PAI of {<=}1 cm and a prostate volume of <50 cc. Two planning studies were done. First, prostate contours were artificially enlarged to 45 to 80 cc in 5- to 10-cc increments for a single subject. Second, all subject prostate contours were enlarged to 60 cc. For each study, three types of plans were manually created for comparison: a parallel needle template (PT) plan, a parallel needle no-template (PNT) plan, and an oblique needle no-template (OBL) plan. Needle positions and angles were not discretized for nontemplate plans. European Society for Therapeutic Radiology and Oncology dose-volume histogram guidelines, iodine-125 (145-Gy prescription, 0.43 U), and needle angles of <15 Degree-Sign were used. An OBL plan was delivered to a pubic arch containing a 60-cc prostate phantom that mimicked the anatomy of the subject with the greatest PAI (23% by volume). Results: In the increasing-prostate volume study, OBL plans were successful for prostates of {<=}80 cc, and PT plans were successful for prostates of <65 cc. In paired, one-sided t tests for the 60-cc volume study, OBL plans showed dosimetric improvements for all organs compared to both of the parallel type plans (p < 0.05); PNT plans showed a benefit only in planning target volumes receiving more than 100 Gy compared to PT plans. A computed tomography scan of the phantom showed submillimeter seed placement accuracy in all directions. Conclusion: OBL plans were significantly better than parallel plans, and an OBL plan was accurately delivered to a 60-cc

  17. Afterloading: The Technique That Rescued Brachytherapy

    SciTech Connect

    Aronowitz, Jesse N.

    2015-07-01

    Although brachytherapy had been established as a highly effective modality for the treatment of cancer, its application was threatened by mid-20th century due to appreciation of the radiation hazard to health care workers. This review examines how the introduction of afterloading eliminated exposure and ushered in a brachytherapy renaissance.

  18. Brachytherapy in breast cancer: an effective alternative

    PubMed Central

    Chicheł, Adam

    2014-01-01

    Breast conserving surgery (BCS) with following external beam radiation therapy (EBRT) of the conserved breast has become widely accepted in the last decades for the treatment of early invasive breast cancer. The standard technique of EBRT after BCS is to treat the whole breast up to a total dose of 42.5 to 50 Gy. An additional dose is given to treated volume as a boost to a portion of the breast. In the early stage of breast cancer, research has shown that the area requiring radiation treatment to prevent the cancer from local recurrence is the breast tissue that surrounds the area where the initial cancer was removed. Accelerated partial breast irradiation (APBI) is an approach that treats only the lumpectomy bed plus a 1-2 cm margin rather than the whole breast and as a result allows accelerated delivery of the radiation dose in four to five days. There has been a growing interest for APBI and various approaches have been developed under phase I-III clinical studies; these include multicatheter interstitial brachytherapy, balloon catheter brachytherapy, conformal external beam radiation therapy (3D-EBRT) and intra-operative radiation therapy (IORT). Balloon-based brachytherapy approaches include MammoSite, Axxent electronic brachytherapy, Contura, hybrid brachytherapy devices. Another indication for breast brachytherapy is reirradiation of local recurrence after mastectomy. Published results of brachytherapy are very promising. We discuss the current status, indications, and technical aspects of breast cancer brachytherapy. PMID:26327829

  19. Prostate Brachytherapy in Men {>=}75 Years of Age

    SciTech Connect

    Merrick, Gregory S. Wallner, Kent E.; Galbreath, Robert W.; Butler, Wayne M.; Brammer, Sarah G.; Allen, Zachariah A.; Adamovich, Edward

    2008-10-01

    Purpose: To evaluate cause-specific survival (CSS), biochemical progression-free survival (bPFS), and overall survival (OS) in prostate cancer patients aged {>=}75 years undergoing brachytherapy with or without supplemental therapies. Methods and Materials: Between April 1995 and August 2004, 145 consecutive patients aged {>=}75 years underwent permanent prostate brachytherapy. Median follow-up was 5.8 years. Biochemical progression-free survival was defined by a prostate-specific antigen level {<=}0.40 ng/mL after nadir. Patients with metastatic prostate cancer or hormone-refractory disease without obvious metastases who died of any cause were classified as dead of prostate cancer. All other deaths were attributed to the immediate cause of death. Multiple clinical, treatment, and dosimetric parameters were evaluated for impact on survival. Results: Nine-year CSS, bPFS, and OS rates for the entire cohort were 99.3%, 97.1%, and 64.5%, respectively. None of the evaluated parameters predicted for CSS, whereas bPFS was most closely predicted by percentage positive biopsies. Overall survival and non-cancer deaths were best predicted by tobacco status. Thirty-seven patients have died, with 83.8% of the deaths due to cardiovascular disease (22 patients) or second malignancies (9 patients). To date, only 1 patient (0.7%) has died of metastatic prostate cancer. Conclusions: After brachytherapy, high rates of CSS and bPFS are noted in elderly prostate cancer patients. Overall, approximately 65% of patients are alive at 9 years, with survival most closely related to tobacco status. We believe our results support an aggressive locoregional approach in appropriately selected elderly patients.

  20. Real-time photoacoustic imaging of prostate brachytherapy seeds using a clinical ultrasound system

    NASA Astrophysics Data System (ADS)

    Kuo, Nathanael; Kang, Hyun Jae; Song, Danny Y.; Kang, Jin U.; Boctor, Emad M.

    2012-06-01

    Prostate brachytherapy is a popular prostate cancer treatment option that involves the permanent implantation of radioactive seeds into the prostate. However, contemporary brachytherapy procedure is limited by the lack of an imaging system that can provide real-time seed-position feedback. While many other imaging systems have been proposed, photoacoustic imaging has emerged as a potential ideal modality to address this need, since it could easily be incorporated into the current ultrasound system used in the operating room. We present such a photoacoustic imaging system built around a clinical ultrasound system to achieve the task of visualizing and localizing seeds. We performed several experiments to analyze the effects of various parameters on the appearance of brachytherapy seeds in photoacoustic images. We also imaged multiple seeds in an ex vivo dog prostate phantom to demonstrate the possibility of using this system in a clinical setting. Although still in its infancy, these initial results of a photoacoustic imaging system for the application of prostate brachytherapy seed localization are highly promising.

  1. Intraoperative high-dose-rate brachytherapy: An American Brachytherapy Society consensus report.

    PubMed

    Lloyd, S; Alektiar, K M; Nag, S; Huang, Y J; Deufel, C L; Mourtada, F; Gaffney, D K

    This report presents recommendations from the American Brachytherapy Society for the use of intraoperative high-dose-rate (IOHDR) brachytherapy. Members of the American Brachytherapy Society with expertise in IOHDR formulated this document based on their clinical experience and a review of the literature. This report covers the use of IOHDR in colorectal cancer, soft tissue sarcoma, gynecologic cancers, head and neck cancers, and pediatric cancers. This report does not cover intraoperative brachytherapy for breast cancer. Details about treatment planning and delivery are emphasized so this document can serve as a guide to practices implementing this technique. IOHDR brachytherapy is generally most beneficial for patients with either close or positive margins and/or recurrent disease in a previous resection bed or previously irradiated area. IOHDR brachytherapy requires a well-coordinated multidisciplinary team. IOHDR brachytherapy is recommended in the treatment of both recurrent and primary locally advanced disease for colorectal and gynecologic malignancies, soft tissue sarcoma, and selected head and neck and pediatric malignancies. Other techniques such as perioperative fractionated brachytherapy are also acceptable in many cases with some advantages and disadvantages compared to IOHDR. IOHDR brachytherapy is a specialized technique in radiation therapy with unique properties and advantages in cancer control. Special considerations for treatment planning and delivery are outlined herein. Copyright © 2017 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  2. Dynamic rotating-shield brachytherapy

    SciTech Connect

    Liu, Yunlong; Flynn, Ryan T.; Kim, Yusung; Yang, Wenjun; Wu, Xiaodong

    2013-12-15

    Purpose: To present dynamic rotating shield brachytherapy (D-RSBT), a novel form of high-dose-rate brachytherapy (HDR-BT) with electronic brachytherapy source, where the radiation shield is capable of changing emission angles during the radiation delivery process.Methods: A D-RSBT system uses two layers of independently rotating tungsten alloy shields, each with a 180° azimuthal emission angle. The D-RSBT planning is separated into two stages: anchor plan optimization and optimal sequencing. In the anchor plan optimization, anchor plans are generated by maximizing the D{sub 90} for the high-risk clinical-tumor-volume (HR-CTV) assuming a fixed azimuthal emission angle of 11.25°. In the optimal sequencing, treatment plans that most closely approximate the anchor plans under the delivery-time constraint will be efficiently computed. Treatment plans for five cervical cancer patients were generated for D-RSBT, single-shield RSBT (S-RSBT), and {sup 192}Ir-based intracavitary brachytherapy with supplementary interstitial brachytherapy (IS + ICBT) assuming five treatment fractions. External beam radiotherapy doses of 45 Gy in 25 fractions of 1.8 Gy each were accounted for. The high-risk clinical target volume (HR-CTV) doses were escalated such that the D{sub 2cc} of the rectum, sigmoid colon, or bladder reached its tolerance equivalent dose in 2 Gy fractions (EQD2 with α/β= 3 Gy) of 75 Gy, 75 Gy, or 90 Gy, respectively.Results: For the patients considered, IS + ICBT had an average total dwell time of 5.7 minutes/fraction (min/fx) assuming a 10 Ci{sup 192}Ir source, and the average HR-CTV D{sub 90} was 78.9 Gy. In order to match the HR-CTV D{sub 90} of IS + ICBT, D-RSBT required an average of 10.1 min/fx more delivery time, and S-RSBT required 6.7 min/fx more. If an additional 20 min/fx of delivery time is allowed beyond that of the IS + ICBT case, D-RSBT and S-RSBT increased the HR-CTV D{sub 90} above IS + ICBT by an average of 16.3 Gy and 9.1 Gy, respectively

  3. Testicular shielding in penile brachytherapy

    PubMed Central

    Bindal, Arpita; Tambe, Chandrashekhar M.; Ghadi, Yogesh; Murthy, Vedang; Shrivastava, Shyam Kishore

    2015-01-01

    Purpose Penile cancer, although rare, is one of the common genitourinary cancers in India affecting mostly aged uncircumcised males. For patients presenting with small superficial lesions < 3 cm restricted to glans, surgery, radical external radiation or brachytherapy may be offered, the latter being preferred as it allows organ and function preservation. In patients receiving brachytherapy, testicular morbidity is not commonly addressed. With an aim to minimize and document the doses to testis after adequate shielding during radical interstitial brachytherapy for penile cancers, we undertook this study in 2 patients undergoing brachytherapy and forms the basis of this report. Material and methods Two patients with early stage penile cancer limited to the glans were treated with radical high-dose-rate (HDR) brachytherapy using interstitial implant. A total of 7-8 tubes were implanted in two planes, parallel to the penile shaft. A total dose of 44-48 Gy (55-60 Gy EQD2 doses with α/β = 10) was delivered in 11-12 fractions of 4 Gy each delivered twice daily. Lead sheets adding to 11 mm (4-5 half value layer) were interposed between the penile shaft and scrotum. The testicular dose was measured using thermoluminescent dosimeters. For each patient, dosimetry was done for 3 fractions and mean calculated. Results The cumulative testicular dose to left and right testis was 31.68 cGy and 42.79 cGy for patient A, and 21.96 cGy and 23.28 cGy for patient B. For the same patients, the mean cumulative dose measured at the posterior aspect of penile shaft was 722.15 cGy and 807.72 cGy, amounting to 16.4% and 16.8% of the prescribed dose. Hence, the application of lead shield 11 mm thick reduced testicular dose from 722-808 cGy to 21.96-42.57 cGy, an “absolute reduction” of 95.99 ± 1.5%. Conclusions With the use of a simple lead shield as described, we were able to effectively reduce testicular dose from “spermicidal” range to “oligospermic” range with possible

  4. Dynamic rotating-shield brachytherapy

    PubMed Central

    Liu, Yunlong; Flynn, Ryan T.; Kim, Yusung; Yang, Wenjun; Wu, Xiaodong

    2013-01-01

    Purpose: To present dynamic rotating shield brachytherapy (D-RSBT), a novel form of high-dose-rate brachytherapy (HDR-BT) with electronic brachytherapy source, where the radiation shield is capable of changing emission angles during the radiation delivery process. Methods: A D-RSBT system uses two layers of independently rotating tungsten alloy shields, each with a 180° azimuthal emission angle. The D-RSBT planning is separated into two stages: anchor plan optimization and optimal sequencing. In the anchor plan optimization, anchor plans are generated by maximizing the D90 for the high-risk clinical-tumor-volume (HR-CTV) assuming a fixed azimuthal emission angle of 11.25°. In the optimal sequencing, treatment plans that most closely approximate the anchor plans under the delivery-time constraint will be efficiently computed. Treatment plans for five cervical cancer patients were generated for D-RSBT, single-shield RSBT (S-RSBT), and 192Ir-based intracavitary brachytherapy with supplementary interstitial brachytherapy (IS + ICBT) assuming five treatment fractions. External beam radiotherapy doses of 45 Gy in 25 fractions of 1.8 Gy each were accounted for. The high-risk clinical target volume (HR-CTV) doses were escalated such that the D2cc of the rectum, sigmoid colon, or bladder reached its tolerance equivalent dose in 2 Gy fractions (EQD2 with α/β = 3 Gy) of 75 Gy, 75 Gy, or 90 Gy, respectively. Results: For the patients considered, IS + ICBT had an average total dwell time of 5.7 minutes/fraction (min/fx) assuming a 10 Ci192Ir source, and the average HR-CTV D90 was 78.9 Gy. In order to match the HR-CTV D90 of IS + ICBT, D-RSBT required an average of 10.1 min/fx more delivery time, and S-RSBT required 6.7 min/fx more. If an additional 20 min/fx of delivery time is allowed beyond that of the IS + ICBT case, D-RSBT and S-RSBT increased the HR-CTV D90 above IS + ICBT by an average of 16.3 Gy and 9.1 Gy, respectively. Conclusions: For cervical cancer patients, D

  5. Dynamic rotating-shield brachytherapy.

    PubMed

    Liu, Yunlong; Flynn, Ryan T; Kim, Yusung; Yang, Wenjun; Wu, Xiaodong

    2013-12-01

    To present dynamic rotating shield brachytherapy (D-RSBT), a novel form of high-dose-rate brachytherapy (HDR-BT) with electronic brachytherapy source, where the radiation shield is capable of changing emission angles during the radiation delivery process. A D-RSBT system uses two layers of independently rotating tungsten alloy shields, each with a 180° azimuthal emission angle. The D-RSBT planning is separated into two stages: anchor plan optimization and optimal sequencing. In the anchor plan optimization, anchor plans are generated by maximizing the D90 for the high-risk clinical-tumor-volume (HR-CTV) assuming a fixed azimuthal emission angle of 11.25°. In the optimal sequencing, treatment plans that most closely approximate the anchor plans under the delivery-time constraint will be efficiently computed. Treatment plans for five cervical cancer patients were generated for D-RSBT, single-shield RSBT (S-RSBT), and (192)Ir-based intracavitary brachytherapy with supplementary interstitial brachytherapy (IS + ICBT) assuming five treatment fractions. External beam radiotherapy doses of 45 Gy in 25 fractions of 1.8 Gy each were accounted for. The high-risk clinical target volume (HR-CTV) doses were escalated such that the D2cc of the rectum, sigmoid colon, or bladder reached its tolerance equivalent dose in 2 Gy fractions (EQD2 with α∕β = 3 Gy) of 75 Gy, 75 Gy, or 90 Gy, respectively. For the patients considered, IS + ICBT had an average total dwell time of 5.7 minutes∕fraction (min∕fx) assuming a 10 Ci(192)Ir source, and the average HR-CTV D90 was 78.9 Gy. In order to match the HR-CTV D90 of IS + ICBT, D-RSBT required an average of 10.1 min∕fx more delivery time, and S-RSBT required 6.7 min∕fx more. If an additional 20 min∕fx of delivery time is allowed beyond that of the IS + ICBT case, D-RSBT and S-RSBT increased the HR-CTV D90 above IS + ICBT by an average of 16.3 Gy and 9.1 Gy, respectively. For cervical cancer patients, D-RSBT can boost HR-CTV D90

  6. Low dose rate brachytherapy (LDR-BT) as monotherapy for early stage prostate cancer in Italy: practice and outcome analysis in a series of 2237 patients from 11 institutions

    PubMed Central

    Fellin, Giovanni; Mirri, Maria A; Santoro, Luigi; Divan, Claudio; Mussari, Salvatore; Ziglio, Francesco; La Face, Beniamino; Barbera, Fernando; Buglione, Michela; Bandera, Laura; Ghedi, Barbara; Di Muzio, Nadia G; Losa, Andrea; Mangili, Paola; Nava, Luciano; Chiarlone, Renato; Ciscognetti, Nunzia; Gastaldi, Emilio; Cattani, Federica; Spoto, Ruggero; Vavassori, Andrea; Giglioli, Francesca R; Guarneri, Alessia; Cerboneschi, Valentina; Mignogna, Marcello; Paoluzzi, Mauro; Ravaglia, Valentina; Chiumento, Costanza; Clemente, Stefania; Fusco, Vincenzo; Santini, Roberto; Stefanacci, Marco; Mangiacotti, Francesco P; Martini, Marco; Palloni, Tiziana; Schinaia, Giuseppe; Lazzari, Grazia; Silvano, Giovanni; Magrini, Stefano; Ricardi, Umberto; Santoni, Riccardo; Orecchia, Roberto

    2016-01-01

    Objective: Low-dose-rate brachytherapy (LDR-BT) in localized prostate cancer is available since 15 years in Italy. We realized the first national multicentre and multidisciplinary data collection to evaluate LDR-BT practice, given as monotherapy, and outcome in terms of biochemical failure. Methods: Between May 1998 and December 2011, 2237 patients with early-stage prostate cancer from 11 Italian community and academic hospitals were treated with iodine-125 (125I) or palladium-103 LDR-BT as monotherapy and followed up for at least 2 years. 125I seeds were implanted in 97.7% of the patients: the mean dose received by 90% of target volume was 145 Gy; the mean target volume receiving 100% of prescribed dose (V100) was 91.1%. Biochemical failure-free survival (BFFS), disease-specific survival (DSS) and overall survival (OS) were estimated using Kaplan–Meier method. Log-rank test and multivariable Cox regression were used to evaluate the relationship of covariates with outcomes. Results: Median follow-up time was 65 months. 5- and 7-year DSS, OS and BFFS were 99 and 98%, 94 and 89%, and 92 and 88%, respectively. At multivariate analysis, the National Comprehensive Cancer Network score (p < 0.0001) and V100 (p = 0.09) were correlated with BFFS, with V100 effect significantly different between patients at low risk and those at intermediate/high risk (p = 0.04). Short follow-up and lack of toxicity data represent the main limitations for a global evaluation of LDR-BT. Conclusion: This first multicentre Italian report confirms LDR-BT as an excellent curative modality for low-/intermediate-risk prostate cancer. Advances in knowledge: Multidisciplinary teams may help to select adequately patients to be treated with brachytherapy, with a direct impact on the implant quality and, possibly, on outcome. PMID:27384381

  7. Low dose rate brachytherapy (LDR-BT) as monotherapy for early stage prostate cancer in Italy: practice and outcome analysis in a series of 2237 patients from 11 institutions.

    PubMed

    Fellin, Giovanni; Mirri, Maria A; Santoro, Luigi; Jereczek-Fossa, Barbara A; Divan, Claudio; Mussari, Salvatore; Ziglio, Francesco; La Face, Beniamino; Barbera, Fernando; Buglione, Michela; Bandera, Laura; Ghedi, Barbara; Di Muzio, Nadia G; Losa, Andrea; Mangili, Paola; Nava, Luciano; Chiarlone, Renato; Ciscognetti, Nunzia; Gastaldi, Emilio; Cattani, Federica; Spoto, Ruggero; Vavassori, Andrea; Giglioli, Francesca R; Guarneri, Alessia; Cerboneschi, Valentina; Mignogna, Marcello; Paoluzzi, Mauro; Ravaglia, Valentina; Chiumento, Costanza; Clemente, Stefania; Fusco, Vincenzo; Santini, Roberto; Stefanacci, Marco; Mangiacotti, Francesco P; Martini, Marco; Palloni, Tiziana; Schinaia, Giuseppe; Lazzari, Grazia; Silvano, Giovanni; Magrini, Stefano; Ricardi, Umberto; Santoni, Riccardo; Orecchia, Roberto

    2016-09-01

    Low-dose-rate brachytherapy (LDR-BT) in localized prostate cancer is available since 15 years in Italy. We realized the first national multicentre and multidisciplinary data collection to evaluate LDR-BT practice, given as monotherapy, and outcome in terms of biochemical failure. Between May 1998 and December 2011, 2237 patients with early-stage prostate cancer from 11 Italian community and academic hospitals were treated with iodine-125 ((125)I) or palladium-103 LDR-BT as monotherapy and followed up for at least 2 years. (125)I seeds were implanted in 97.7% of the patients: the mean dose received by 90% of target volume was 145 Gy; the mean target volume receiving 100% of prescribed dose (V100) was 91.1%. Biochemical failure-free survival (BFFS), disease-specific survival (DSS) and overall survival (OS) were estimated using Kaplan-Meier method. Log-rank test and multivariable Cox regression were used to evaluate the relationship of covariates with outcomes. Median follow-up time was 65 months. 5- and 7-year DSS, OS and BFFS were 99 and 98%, 94 and 89%, and 92 and 88%, respectively. At multivariate analysis, the National Comprehensive Cancer Network score (p < 0.0001) and V100 (p = 0.09) were correlated with BFFS, with V100 effect significantly different between patients at low risk and those at intermediate/high risk (p = 0.04). Short follow-up and lack of toxicity data represent the main limitations for a global evaluation of LDR-BT. This first multicentre Italian report confirms LDR-BT as an excellent curative modality for low-/intermediate-risk prostate cancer. Multidisciplinary teams may help to select adequately patients to be treated with brachytherapy, with a direct impact on the implant quality and, possibly, on outcome.

  8. High dose rate brachytherapy for oral cancer

    PubMed Central

    YamazakI, Hideya; Yoshida, Ken; Yoshioka, Yasuo; Shimizutani, Kimishige; Furukawa, Souhei; Koizumi, Masahiko; Ogawa, Kazuhiko

    2013-01-01

    Brachytherapy results in better dose distribution compared with other treatments because of steep dose reduction in the surrounding normal tissues. Excellent local control rates and acceptable side effects have been demonstrated with brachytherapy as a sole treatment modality, a postoperative method, and a method of reirradiation. Low-dose-rate (LDR) brachytherapy has been employed worldwide for its superior outcome. With the advent of technology, high-dose-rate (HDR) brachytherapy has enabled health care providers to avoid radiation exposure. This therapy has been used for treating many types of cancer such as gynecological cancer, breast cancer, and prostate cancer. However, LDR and pulsed-dose-rate interstitial brachytherapies have been mainstays for head and neck cancer. HDR brachytherapy has not become widely used in the radiotherapy community for treating head and neck cancer because of lack of experience and biological concerns. On the other hand, because HDR brachytherapy is less time-consuming, treatment can occasionally be administered on an outpatient basis. For the convenience and safety of patients and medical staff, HDR brachytherapy should be explored. To enhance the role of this therapy in treatment of head and neck lesions, we have reviewed its outcomes with oral cancer, including Phase I/II to Phase III studies, evaluating this technique in terms of safety and efficacy. In particular, our studies have shown that superficial tumors can be treated using a non-invasive mold technique on an outpatient basis without adverse reactions. The next generation of image-guided brachytherapy using HDR has been discussed. In conclusion, although concrete evidence is yet to be produced with a sophisticated study in a reproducible manner, HDR brachytherapy remains an important option for treatment of oral cancer. PMID:23179377

  9. Essure Permanent Birth Control

    MedlinePlus

    ... and Prosthetics Essure Permanent Birth Control Essure Permanent Birth Control Share Tweet Linkedin Pin it More sharing options ... Essure System Essure is a a permanently implanted birth control device for women (female sterilization). Implantation of Essure ...

  10. Dose to the Bladder Neck Is the Most Important Predictor for Acute and Late Toxicity After Low-Dose-Rate Prostate Brachytherapy: Implications for Establishing New Dose Constraints for Treatment Planning

    SciTech Connect

    Hathout, Lara; Folkert, Michael R.; Kollmeier, Marisa A.; Yamada, Yoshiya; Cohen, Gil'ad N.; Zelefsky, Michael J.

    2014-10-01

    Purpose: To identify an anatomic structure predictive for acute (AUT) and late (LUT) urinary toxicity in patients with prostate cancer treated with low-dose-rate brachytherapy (LDR) with or without external beam radiation therapy (EBRT). Methods and Materials: From July 2002 to January 2013, 927 patients with prostate cancer (median age, 66 years) underwent LDR brachytherapy with Iodine 125 (n=753) or Palladium 103 (n=174) as definitive treatment (n=478) and as a boost (n=449) followed by supplemental EBRT (median dose, 50.4 Gy). Structures contoured on the computed tomographic (CT) scan on day 0 after implantation included prostate, urethra, bladder, and the bladder neck, defined as 5 mm around the urethra between the catheter balloon and the prostatic urethra. AUT and LUT were assessed with the Common Terminology Criteria for Adverse Events, version4. Clinical and dosimetric factors associated with AUT and LUT were analyzed with Cox regression and receiver operating characteristic analysis to calculate area under the receiver operator curve (ROC) (AUC). Results: Grade ≥2 AUT and grade ≥2 LUT occurred in 520 patients (56%) and 154 patients (20%), respectively. No grade 4 toxicities were observed. Bladder neck D2cc retained a significant association with AUT (hazard ratio [HR], 1.03; 95% confidence interval [CI], 1.03-1.04; P<.0001) and LUT (HR, 1.01; 95% CI, 1.00-1.03; P=.014) on multivariable analysis. In a comparison of bladder neck with the standard dosimetric variables by use of ROC analysis (prostate V100 >90%, D90 >100%, V150 >60%, urethra D20 >130%), bladder neck D2cc >50% was shown to have the strongest prognostic power for AUT (AUC, 0.697; P<.0001) and LUT (AUC, 0.620; P<.001). Conclusions: Bladder neck D2cc >50% was the strongest predictor for grade ≥2 AUT and LUT in patients treated with LDR brachytherapy. These data support inclusion of bladder neck constraints into brachytherapy planning to decrease urinary toxicity.

  11. American Brachytherapy Society recommendations for reporting morbidity after prostate brachytherapy.

    PubMed

    Nag, Subir; Ellis, Rodney J; Merrick, Gregory S; Bahnson, Robert; Wallner, Kent; Stock, Richard

    2002-10-01

    To standardize the reporting of brachytherapy-related prostate morbidity to guide ongoing clinical practice and future investigations. Members of the American Brachytherapy Society (ABS) with expertise in prostate brachytherapy performed a literature review and, guided by their clinical experience, formulated specific recommendations for reporting on morbidity related to prostate brachytherapy. The ABS recommends using validated, patient-administered health-related quality-of-life instruments for the determination of baseline and follow-up data regarding bowel, urinary, and sexual function. Both actuarial and crude incidences should be reported, along with the temporal resolution of specific complications, and correlated with the doses to the normal tissues. The International Prostate Symptom Score is recommended to assess urinary morbidity, and any dysuria, gross hematuria, urinary retention, incontinence, or medication use should be quantified. Likewise, the "Sexual Health Inventory for Men," which includes the specific erectile questions of the International Index of Erectile Function, is the preferred instrument for reporting sexual function, and the loss of sexual desire, incidence of hematospermia, painful orgasm (orgasmalgia), altered orgasm intensity, decreased ejaculatory volume, use of erectile aids, and use of hormones for androgen deprivation should be quantified. The ABS recommends adoption of the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer acute and late radiation morbidity scoring scheme for reporting rectal morbidity and noting the incidence of rectal steroid, laser, or antidiarrheal use. It is important to focus on health-related quality-of-life issues in the treatment of prostate cancer, because the control rates are very similar between appropriate treatment modalities. The ABS recommends using the International Prostate Symptom Score, International Index of Erectile Function, and Radiation Therapy

  12. Tissue modeling schemes in low energy breast brachytherapy

    NASA Astrophysics Data System (ADS)

    Afsharpour, Hossein; Landry, Guillaume; Reniers, Brigitte; Pignol, Jean-Philippe; Beaulieu, Luc; Verhaegen, Frank

    2011-11-01

    Breast tissue is heterogeneous and is mainly composed of glandular (G) and adipose (A) tissues. The proportion of G versus A varies considerably among the population. The absorbed dose distributions in accelerated partial breast irradiation therapy with low energy photon brachytherapy sources are very sensitive to tissue heterogeneities. Current clinical algorithms use the recommendations of the AAPM TG43 report which approximates the human tissues by unit density water. The aim of this study is to investigate various breast tissue modeling schemes for low energy brachytherapy. A special case of breast permanent seed implant is considered here. Six modeling schemes are considered. Uniform and non-uniform water breast (UWB and NUWB) consider the density but neglect the effect of the composition of tissues. The uniform and the non-uniform G/A breast (UGAB and NUGAB) as well the age-dependent breast (ADB) models consider the effect of the composition. The segmented breast tissue (SBT) method uses a density threshold to distinguish between G and A tissues. The PTV D90 metric is used for the analysis and is based on the dose to water (D90(w,m)). D90(m,m) is also reported for comparison to D90(w,m). The two-month post-implant D90(w,m) averaged over 38 patients is smaller in NUWB than in UWB by about 4.6% on average (ranging from 5% to 13%). Large average differences of G/A breast models with TG43 (17% and 26% in UGAB and NUGAB, respectively) show that the effect of the chemical composition dominates the effect of the density on dose distributions. D90(w,m) is 12% larger in SBT than in TG43 when averaged. These differences can be as low as 4% or as high as 20% when the individual patients are considered. The high sensitivity of dosimetry on the modeling scheme argues in favor of an agreement on a standard tissue modeling approach to be used in low energy breast brachytherapy. SBT appears to generate the most geometrically reliable breast tissue models in this report. This

  13. HDR brachytherapy for anal cancer

    PubMed Central

    Kovács, Gyoergy

    2014-01-01

    The challenge of treating anal cancer is to preserve the anal sphincter function while giving high doses to the tumor and sparing the organ at risk. For that reason there has been a shift from radical surgical treatment with colostomy to conservative treatment. Radiotherapy combined with chemotherapy has an important role in the treatment of anal cancer patients. New techniques as intensity modulated radiotherapy (IMRT) have shown reduced acute toxicity and high rates of local control in combination with chemotherapy compared to conventional 3-D radiotherapy. Not only external beam radio-chemotherapy treatment (EBRT) is an established method for primary treatment of anal cancer, brachytherapy (BT) is also an approved method. BT is well known for boost irradiation in combination with EBRT (+/– chemotherapy). Because of technical developments like modern image based 3D treatment planning and the possibility of intensity modulation in brachytherapy (IMBT), BT today has even more therapeutic potential than it had in the era of linear sources. The combination of external beam radiotherapy (EBRT) and BT allows the clinician to deliver higher doses to the tumor and to reduce dose to the normal issue. Improvements in local control and reductions in toxicity therefore become possible. Various BT techniques and their results are discussed in this work. PMID:24982770

  14. LDR brachytherapy: can low dose rate hypersensitivity from the "inverse" dose rate effect cause excessive cell killing to peripherial connective tissues and organs?

    PubMed

    Leonard, B E; Lucas, A C

    2009-02-01

    Examined here are the possible effects of the "inverse" dose rate effect (IDRE) on low dose rate (LDR) brachytherapy. The hyper-radiosensitivity and induced radioresistance (HRS/IRR) effect benefits cell killing in radiotherapy, and IDRE and HRS/IRR seem to be generated from the same radioprotective mechanisms. We have computed the IDRE excess cell killing experienced in LDR brachytherapy using permanent seed implants. We conclude, firstly, that IDRE is a dose rate-dependent manifestation of HRS/IRR. Secondly, the presence of HRS/IRR or IDRE in a cell species or tissue must be determined by direct dose-response measurements. Thirdly, a reasonable estimate is that 50-80% of human adjoining connective and organ tissues experience IDRE from permanent implanted LDR brachytherapy. If IDRE occurs for tissues at point A for cervical cancer, the excess cell killing will be about a factor of 3.5-4.0 if the initial dose rate is 50-70 cGy h(-1). It is greater for adjacent tissues at lower dose rates and higher for lower initial dose rates at point A. Finally, higher post-treatment complications are observed in LDR brachytherapy, often for unknown reasons. Some of these are probably a result of IDRE excess cell killing. Measurements of IDRE need be performed for connective and adjacent organ tissues, i.e. bladder, rectum, urinary tract and small bowels. The measured dose rate-dependent dose responses should extended to <10 cGy h(-1) and involve multiple patients to detect patient variability. Results may suggest a preference for high dose rate brachytherapy or LDR brachytherapy without permanent retention of the implant seeds (hence the dose rates in peripheral tissues and organs remain above IDRE thresholds).

  15. Characterization of Low-Energy Photon-Emitting Brachytherapy Sources with Modified Strengths for Applications in Focal Therapy

    NASA Astrophysics Data System (ADS)

    Reed, Joshua L.

    Permanent implants of low-energy photon-emitting brachytherapy sources are used to treat a variety of cancers. Individual source models must be separately characterized due to their unique geometry, materials, and radionuclides, which all influence their dose distributions. Thermoluminescent dosimeters (TLDs) are often used for dose measurements around low-energy photon-emitting brachytherapy sources. TLDs are typically calibrated with higher energy sources such as 60Co, which requires a correction for the change in the response of the TLDs as a function of photon energy. These corrections have historically been based on TLD response to x ray bremsstrahlung spectra instead of to brachytherapy sources themselves. This work determined the TLD intrinsic energy dependence for 125I and 103Pd sources relative to 60Co, which allows for correction of TLD measurements of brachytherapy sources with factors specific to their energy spectra. Traditional brachytherapy sources contain mobile internal components and large amounts of high-Z material such as radio-opaque markers and titanium encapsulations. These all contribute to perturbations and uncertainties in the dose distribution around the source. The CivaString is a new elongated 103Pd brachytherapy source with a fixed internal geometry, polymer encapsulation, and lengths ranging from 1 to 6 cm, which offers advantages over traditional source designs. This work characterized the CivaString source and the results facilitated the formal approval of this source for use in clinical treatments. Additionally, the accuracy of a superposition technique for dose calculation around the sources with lengths >1 cm was verified. Advances in diagnostic techniques are paving the way for focal brachytherapy in which the dose is intentionally modulated throughout the target volume to focus on subvolumes that contain cancer cells. Brachytherapy sources with variable longitudinal strength (VLS) are a promising candidate for use in focal

  16. Long duration mild temperature hyperthermia and brachytherapy.

    PubMed

    Armour, E P; Raaphorst, G P

    2004-03-01

    Combining long duration mild temperature hyperthermia (LDMH) and low dose-rate (LDR) brachytherapy to enhance therapeutic killing of cancer cells was proposed many years ago. The cellular and tumour research that supports this hypothesis is presented in this review. Research describing LDMH interaction with pulsed brachytherapy and high dose-rate brachytherapy using clinically relevant parameters are compared with LDMH/LDR brachytherapy. The mechanism by which LDMH sensitizes LDR has been established as the inhibition of sublethal damage repair. The molecular mechanisms have been shown to involve DNA repair enzymes, but the exact nature of these processes is still under investigation. The relative differences between LDMH interactions with human and rodent cells are presented to help in the understanding of possible roles of LDMH in clinical application. The role of LDMH in modifying tumour blood flow and its possible role in LDR sensitization of tumours is also presented. The positive aspects of LDMH-brachytherapy for clinical application are sixfold; (1) the thermal goals (temperature, time and volume) are achievable with currently available technology, (2) the hyperthermia by itself has no detectable toxic effects, (3) thermotolerance appears to play a minor if any role in radiation sensitization, (4) TER of around 2 can be expected, (5) hypoxic fraction may be decreased due to blood flow modification and (6) simultaneous chemotherapy may also be sensitized. Combined LDMH and brachytherapy is a cancer therapy that has established biological rationale and sufficient technical and clinical advancements to be appropriately applied. This modality is ripe for clinical testing.

  17. Adjuvant stereotactic permanent seed breast implant: A boost series in view of partial breast irradiation

    SciTech Connect

    Jansen, Nicolas . E-mail: nicolas.jansen@chu.ulg.ac.be; Deneufbourg, Jean-Marie; Nickers, Philippe

    2007-03-15

    Purpose: The aim of this study was to use permanent seed implants in the breast and describe our experience with 15 cases, using iodine seed implants as a tumor bed boost. Methods and Materials: Breasts were fixed with a thermoplastic sheet, a template bridge applied, the thorax scanned and the images rotated to be perpendicular to the implant axis. Skin, heart, and lung were delineated. A preplan was made, prescribing 50 Gy to the clinical target volume (CTV), consisting in this boost series of nearly a quadrant. Iodine (125) seeds were stereotactically implanted through the template, and results were checked with a postplan computed tomographic (CT) scan. Results: The breast was immobilized reproducibly. Simulation, scanning, and implant were performed without difficulties. Preplan CTV D90% (the dose delivered to 90% of the CTV) was 66 Gy, and postoperative fluoroscopic or CT scan checks were satisfactory. Pre- and postplan dose-volume histogram showed good organ sparing: mean postplan skin, heart, and lung V30 Gy (the organ volume receiving a dose of 30 Gy) of 2 {+-} 2.2 mL, 0.24 {+-} 0.34 mL, and 3.5 {+-} 5 mL, respectively. No short-term toxicity above Grade 1 was noted, except for transient Grade 3 neuropathy in 1 patient. Conclusions: Seeds remained in the right place, as assessed by fluoroscopy, absence of significant pre- to postplan dose-volume histogram change for critical organs, and total irradiated breast volume. The method could be proposed as a boost when high dosimetric selectivity is required (young patients after cardiotoxic chemotherapy for left-sided cancer). This boost series was a preliminary step before testing partial breast irradiation by permanent seed implant in a prospective trial.

  18. 10 CFR 35.406 - Brachytherapy sources accountability.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Brachytherapy sources accountability. 35.406 Section 35.406 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35... for all brachytherapy sources in storage or use. (b) As soon as possible after removing sources from...

  19. 10 CFR 35.406 - Brachytherapy sources accountability.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 1 2012-01-01 2012-01-01 false Brachytherapy sources accountability. 35.406 Section 35.406 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35... for all brachytherapy sources in storage or use. (b) As soon as possible after removing sources from...

  20. 10 CFR 35.406 - Brachytherapy sources accountability.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Brachytherapy sources accountability. 35.406 Section 35.406 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35... for all brachytherapy sources in storage or use. (b) As soon as possible after removing sources from...

  1. 10 CFR 35.406 - Brachytherapy sources accountability.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Brachytherapy sources accountability. 35.406 Section 35.406 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35... for all brachytherapy sources in storage or use. (b) As soon as possible after removing sources from...

  2. 10 CFR 35.406 - Brachytherapy sources accountability.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Brachytherapy sources accountability. 35.406 Section 35.406 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35... for all brachytherapy sources in storage or use. (b) As soon as possible after removing sources from...

  3. Dosimetric Characteristics for Brachytherapy Sources

    SciTech Connect

    DeWerd, Larry A.; Davis, Stephen D.

    2011-05-05

    Brachytherapy sources are characterized by the dosimetric parameters in a protocol such as the American Association of Physicists in Medicine Task Group 43. The air-kerma strength is measured and traceable to a primary standard. Then the parameters such as dose-rate constant, radial dose function, and anisotropy function are measured and related back to the primary standard. This is normally accomplished with thermoluminescent dosimeters (TLDs). Since radial dose function and anisotropy function are relative parameters, some of the dosimetric corrections are negligible. For the dose-rate constant, parameters such as the energy dependence compared with a calibration beam such as {sup 60}Co need to be accounted for. A description of the primary standard measurements and TLD measurements will be discussed.

  4. Brachytherapy next generation: robotic systems

    PubMed Central

    Popescu, Tiberiu; Kacsó, Alex Cristian; Pisla, Doina

    2015-01-01

    In a field dominated by external beam radiation therapy (EBRT), both the therapeutic and technical possibilities of brachytherapy (BT) are underrated, shadowed by protons and intensity modulated radiotherapy. Decreasing expertise and indications, as well as increasing lack of specific BT training for radiation therapy (RT) residents led to the real need of shortening its learning curve and making it more popular. Developing robotic BT devices can be a way to mitigate the above issues. There are many teams working at custom-made robotic BT platforms to perfect and overcome the limitations of the existing systems. This paper provides a picture of the current state-of-the-art in robotic assisted BT, as it also conveys the author's solution to the problem, a parallel robot that uses CT-guidance. PMID:26816510

  5. In vivo dosimetry in brachytherapy

    SciTech Connect

    Tanderup, Kari; Beddar, Sam; Andersen, Claus E.; Kertzscher, Gustavo; Cygler, Joanna E.

    2013-07-15

    In vivo dosimetry (IVD) has been used in brachytherapy (BT) for decades with a number of different detectors and measurement technologies. However, IVD in BT has been subject to certain difficulties and complexities, in particular due to challenges of the high-gradient BT dose distribution and the large range of dose and dose rate. Due to these challenges, the sensitivity and specificity toward error detection has been limited, and IVD has mainly been restricted to detection of gross errors. Given these factors, routine use of IVD is currently limited in many departments. Although the impact of potential errors may be detrimental since treatments are typically administered in large fractions and with high-gradient-dose-distributions, BT is usually delivered without independent verification of the treatment delivery. This Vision 20/20 paper encourages improvements within BT safety by developments of IVD into an effective method of independent treatment verification.

  6. APPLICATION III: Permanent Magnet

    NASA Astrophysics Data System (ADS)

    Gotoh, Satoshi

    The following sections are included: * Introduction * Superconducting permanent magnet using pinned type superconductor * Magnetization process based on the critical state * Demagnetizing curve and permanent magnetic properties * Demagnetizing field of pinned type II superconductor * Samples and experiments * Sample preparation * Magnetization measurements * Permanent magnetic properties of the melt processed YBCO * QMG processed YBCO * MPMG processed YBCO * Summary * References

  7. {sup 106}Ruthenium Brachytherapy for Retinoblastoma

    SciTech Connect

    Abouzeid, Hana; Moeckli, Raphael; Gaillard, Marie-Claire; Beck-Popovic, Maja; Pica, Alessia; Zografos, Leonidas; Balmer, Aubin; Pampallona, Sandro; Munier, Francis L.

    2008-07-01

    Purpose: To evaluate the efficacy of {sup 106}Ru plaque brachytherapy for the treatment of retinoblastoma. Methods and Materials: We reviewed a retrospective, noncomparative case series of 39 children with retinoblastoma treated with {sup 106}Ru plaques at the Jules-Gonin Eye Hospital between October 1992 and July 2006, with 12 months of follow-up. Results: A total of 63 tumors were treated with {sup 106}Ru brachytherapy in 41 eyes. The median patient age was 27 months. {sup 106}Ru brachytherapy was the first-line treatment for 3 tumors (4.8%), second-line treatment for 13 (20.6%), and salvage treatment for 47 tumors (74.6%) resistant to other treatment modalities. Overall tumor control was achieved in 73% at 1 year. Tumor recurrence at 12 months was observed in 2 (12.5%) of 16 tumors for which {sup 106}Ru brachytherapy was used as the first- or second-line treatment and in 15 (31.9%) of 47 tumors for which {sup 106}Ru brachytherapy was used as salvage treatment. Eye retention was achieved in 76% of cases (31 of 41 eyes). Univariate and multivariate analyses revealed no statistically significant risk factors for tumor recurrence. Radiation complications included retinal detachment in 7 (17.1%), proliferative retinopathy in 1 (2.4%), and subcapsular cataract in 4 (9.7%) of 41 eyes. Conclusion: {sup 106}Ru brachytherapy is an effective treatment for retinoblastoma, with few secondary complications. Local vitreous seeding can be successfully treated with {sup 106}Ru brachytherapy.

  8. Brachytherapy in the Treatment of Cholangiocarcinoma

    SciTech Connect

    Shinohara, Eric T.; Guo Mengye; Mitra, Nandita; Metz, James M.

    2010-11-01

    Purpose: To examine the role of brachytherapy in the treatment of cholangiocarcinomas in a relatively large group of patients. Methods and Materials: Using the Surveillance, Epidemiology and End Results database, a total of 193 patients with cholangiocarcinoma treated with brachytherapy were identified for the period 1988-2003. The primary analysis compared patients treated with brachytherapy (with or without external-beam radiation) with those who did not receive radiation. To try to account for confounding variables, propensity score and sensitivity analyses were used. Results: There was a significant difference between patients who received radiation (n = 193) and those who did not (n = 6859) with regard to surgery (p < 0.0001), race (p < 0.0001), stage (p < 0.0001), and year of diagnosis (p <0.0001). Median survival for patients treated with brachytherapy was 11 months (95% confidence interval [CI] 9-13 months), compared with 4 months for patients who received no radiation (p < 0.0001). On multivariable analysis (hazard ratio [95% CI]) brachytherapy (0.79 [0.66-0.95]), surgery (0.50 [0.46-0.53]), year of diagnosis (1998-2003: 0.66 [0.60-0.73]; 1993-1997: (0.96 [0.89-1.03; NS], baseline 1988-1992), and extrahepatic disease (0.84 [0.79-0.89]) were associated with better overall survival. Conclusions: To the authors' knowledge, this is the largest dataset reported for the treatment of cholangiocarcinomas with brachytherapy. The results of this retrospective analysis suggest that brachytherapy may improve overall survival. However, because of the limitations of the Surveillance, Epidemiology and End Results database, these results should be interpreted cautiously, and future prospective studies are needed.

  9. Incidence of Second Malignancies in Prostate Cancer Patients Treated With Low-Dose-Rate Brachytherapy and Radical Prostatectomy

    SciTech Connect

    Hamilton, Sarah Nicole; Tyldesley, Scott; Hamm, Jeremy; Jiang, Wei Ning; Keyes, Mira; Pickles, Tom; Lapointe, Vince; Kahnamelli, Adam; McKenzie, Michael; Miller, Stacy; Morris, W. James

    2014-11-15

    Purpose: To compare the second malignancy incidence in prostate cancer patients treated with brachytherapy (BT) relative to radical prostatectomy (RP) and to compare both groups with the cancer incidence in the general population. Methods and Materials: From 1998 to 2010, 2418 patients were treated with Iodine 125 prostate BT monotherapy at the British Columbia Cancer Agency, and 4015 referred patients were treated with RP. Cancer incidence was compared with the age-matched general population using standardized incidence ratios (SIRs). Pelvic malignancies included invasive and noninvasive bladder cancer and rectal cancer. Cox multivariable analysis was performed with adjustment for covariates to determine whether treatment (RP vs BT) was associated with second malignancy risk. Results: The median age at BT was 66 years and at RP 62 years. The SIR comparing BT patients with the general population was 1.06 (95% confidence interval [CI] 0.91-1.22) for second malignancy and was 1.53 (95% CI 1.12-2.04) for pelvic malignancy. The SIR comparing RP patients with the general population was 1.11 (95% CI 0.98-1.25) for second malignancy and was 1.11 (95% CI 0.82-1.48) for pelvic malignancy. On multivariable analysis, older age (hazard ratio [HR] 1.05) and smoking (HR 1.65) were associated with increased second malignancy risk (P<.0001). Radical prostatectomy was not associated with a decreased second malignancy risk relative to BT (HR 0.90, P=.43), even when excluding patients who received postprostatectomy external beam radiation therapy (HR 1.13, P=.25). Older age (HR 1.09, P<.0001) and smoking (HR 2.17, P=.0009) were associated with increased pelvic malignancy risk. Radical prostatectomy was not associated with a decreased pelvic malignancy risk compared with BT (HR 0.57, P=.082), even when excluding postprostatectomy external beam radiation therapy patients (HR 0.87, P=.56). Conclusions: After adjustment for covariates, BT patients did not have an increased second

  10. Late Urinary Side Effects 10 Years After Low-Dose-Rate Prostate Brachytherapy: Population-Based Results From a Multiphysician Practice Treating With a Standardized Protocol and Uniform Dosimetric Goals

    SciTech Connect

    Keyes, Mira Miller, Stacy; Pickles, Tom; Halperin, Ross; Kwan, Winkle; Lapointe, Vincent; McKenzie, Michael; Spadinger, Ingrid; Pai, Howard; Chan, Elisa K.; Morris, W. James

    2014-11-01

    Purpose: To determine late urinary toxicity (>12 months) in a large cohort of uniformly treated low-dose-rate prostate brachytherapy patients. Methods and Materials: From 1998 to 2009, 2709 patients with National Comprehensive Cancer Network–defined low-risk and low-tier intermediate-risk prostate cancer were treated with Iodine 125 ({sup 125}I) low-dose-rate prostate brachytherapy; 2011 patients with a minimum of 25 months of follow-up were included in the study. Baseline patients, treatment, implant factors, and late urinary toxicity (Radiation Therapy Oncology Group [RTOG] grading system and International Prostate Symptom Score [IPSS]) were recorded prospectively. Time to IPSS resolution, late RTOG genitourinary toxicity was examined with Kaplan-Meier and log-rank tests. Cox proportional hazards regression was done for individual covariates and multivariable models. Results: Median follow-up was 54.5 months (range, 2-13 years). Actuarial toxicity rates reached 27% and 10% (RTOG ≥2 and ≥3, respectively) at 9-13 years. Symptoms resolved quickly in the majority of patients (88% in 6-12 months). The prevalence of RTOG 0, 1, 2, 3, and 4 toxicity with a minimum of 7 years' follow-up was 70%, 21%, 6.4%, 2.3%, and 0.08%, respectively. Patients with a larger prostate volume, higher baseline IPSS, higher D90, acute toxicity, and age >70 years had more late RTOG ≥2 toxicity (all P≤.02). The IPSS resolved slower in patients with lower baseline IPSS and larger ultrasound prostate volume, those not receiving androgen deprivation therapy, and those with higher D90. The crude rate of RTOG 3 toxicity was 6%. Overall the rate of transurethral resection of the prostate was 1.9%; strictures, 2%; incontinence, 1.3%; severe symptoms, 1.8%; late catheterization, 1.3%; and hematuria, 0.8%. The majority (80%) resolved their symptoms in 6-12 months. Conclusion: Long-term urinary toxicity after brachytherapy is low. Although actuarial rates increase with longer follow

  11. Rare earth permanent magnets

    SciTech Connect

    Major-Sosias, M.A.

    1993-10-01

    Permanent magnets were discovered centuries ago from what was known as {open_quotes}lodestone{close_quotes}, a rock containing large quantities of the iron-bearing mineral magnetite (Fe{sub 3}O{sub 4}). The compass was the first technological use for permanent magnetic materials; it was used extensively for navigational purposes by the fifteenth century. During the twentieth century, as new applications for permanent magnets were developed, interest and research in permanent magnetic materials soared. Four major types of permanent magnets have been developed since the turn of the century.

  12. Image guided Brachytherapy: The paradigm of Gynecologic and Partial Breast HDR Brachytherapy

    NASA Astrophysics Data System (ADS)

    Diamantopoulos, S.; Kantemiris, I.; Konidari, A.; Zaverdinos, P.

    2015-09-01

    High dose rate (HDR) brachytherapy uses high strength radioactive sources and temporary interstitial implants to conform the dose to target and minimize the treatment time. The advances of imaging technology enable accurate reconstruction of the implant and exact delineation of high-risk CTV and the surrounding critical structures. Furthermore, with sophisticated treatment planning systems, applicator devices and stepping source afterloaders, brachytherapy evolved to a more precise, safe and individualized treatment. At the Radiation Oncology Department of Metropolitan Hospital Athens, MRI guided HDR gynecologic (GYN) brachytherapy and accelerated partial breast irradiation (APBI) with brachytherapy are performed routinely. Contouring and treatment planning are based on the recommendations of the GEC - ESTRO Working group. The task of this presentation is to reveal the advantages of 3D image guided brachytherapy over 2D brachytherapy. Thus, two patients treated at our department (one GYN and one APBI) will be presented. The advantage of having adequate dose coverage of the high risk CTV and simultaneous low doses to the OARs when using 3D image- based brachytherapy will be presented. The treatment techniques, equipment issues, as well as implantation, imaging and treatment planning procedures will be described. Quality assurance checks will be treated separately.

  13. Brachytherapy and Local Excision for Sphincter Preservation in T1 and T2 Rectal Cancer

    SciTech Connect

    Grimard, Laval Stern, Hartley; Spaans, Johanna N. M.Sc.

    2009-07-01

    Purpose: To report long-term results of brachytherapy after local excision (LE) in the treatment of T1 and T2 rectal cancer at risk of recurrence due to residual subclinical disease. Methods and Materials: Between 1989 and 2007, 32 patients undergoing LE and brachytherapy were followed prospectively for a mean of 6.2 years. Estimates of local recurrence (LR), disease-specific survival (DSS), and overall survival (OS) were generated. Treatment-related toxicity and the effect of known prognostic factors were determined. Results: There were 8 LR (3 T1, 5 T2), of which 5 were salvaged surgically. Median time to the 8 LR was 14 months, and the 5-year rate of local control was 76%. Although there have been 9 deaths to date, only 5 were from disease. Five-year DSS and OS rates were 85% and 78%, respectively. There were 4 cases of Grade 2-3 radionecrosis and 1 case of mild stool incontinence. The sphincter was preserved in 27 of 32 patients. Conclusion: Local excision and adjuvant brachytherapy for T1 and T2 rectal cancer is an appealing treatment alternative to immediate radical resection, particularly in the frail and elderly who are unable to undergo major surgery, as well as for patients wanting to avoid a permanent colostomy.

  14. Prostate brachytherapy postimplant dosimetry: Automatic plan reconstruction of stranded implants

    SciTech Connect

    Chng, N.; Spadinger, I.; Morris, W. J.; Usmani, N.; Salcudean, S.

    2011-01-15

    Purpose: Plan reconstruction for permanent implant prostate brachytherapy is the process of determining the correspondence between planned and implanted seeds in postimplant analysis. Plan reconstruction informs many areas of brachytherapy quality assurance, including the verification of seed segmentation, misplacement and migration assessment, implant simulations, and the dosimetry of mixed-activity or mixed-species implants. Methods: An algorithm has been developed for stranded implants which uses the interseed spacing constraints imposed by the suture to improve the accuracy of reconstruction. Seventy randomly selected clinical cases with a mean of 23.6 (range 18-30) needles and mean density of 2.0 (range 1.6-2.6) 2.0 (range 1.6-2.6) seeds/cm{sup 3} were automatically reconstructed and the accuracy compared to manual reconstructions performed using a custom 3D graphical interface. Results: Using the automatic algorithm, the mean accuracy of the assignment relative to manual reconstruction was found to be 97.7{+-}0.5%. Fifty-two of the 70 cases (74%) were error-free; of seeds in the remaining cases, 96.7{+-}0.3% were found to be attributed to the correct strand and 97.0{+-}0.3% were correctly connected to their neighbors. Any necessary manual correction using the interface is usually straightforward. For the clinical data set tested, neither the number of seeds or needles, average density, nor the presence of clusters was found to have an effect on reconstruction accuracy using this method. Conclusions: Routine plan reconstruction of stranded implants can be performed with a high degree of accuracy to support postimplant dosimetry and quality analyses.

  15. Cervix cancer brachytherapy: high dose rate.

    PubMed

    Miglierini, P; Malhaire, J-P; Goasduff, G; Miranda, O; Pradier, O

    2014-10-01

    Cervical cancer, although less common in industrialized countries, is the fourth most common cancer affecting women worldwide and the fourth leading cause of cancer death. In developing countries, these cancers are often discovered at a later stage in the form of locally advanced tumour with a poor prognosis. Depending on the stage of the disease, treatment is mainly based on a chemoradiotherapy followed by uterovaginal brachytherapy ending by a potential remaining tumour surgery or in principle for some teams. The role of irradiation is crucial to ensure a better local control. It has been shown that the more the delivered dose is important, the better the local results are. In order to preserve the maximum of organs at risk and to allow this dose escalation, brachytherapy (intracavitary and/or interstitial) has been progressively introduced. Its evolution and its progressive improvement have led to the development of high dose rate brachytherapy, the advantages of which are especially based on the possibility of outpatient treatment while maintaining the effectiveness of other brachytherapy forms (i.e., low dose rate or pulsed dose rate). Numerous innovations have also been completed in the field of imaging, leading to a progress in treatment planning systems by switching from two-dimensional form to a three-dimensional one. Image-guided brachytherapy allows more precise target volume delineation as well as an optimized dosimetry permitting a better coverage of target volumes.

  16. Interstitial hyperthermia in combination with brachytherapy.

    PubMed

    Coughlin, C T; Douple, E B; Strohbehn, J W; Eaton, W L; Trembly, B S; Wong, T Z

    1983-07-01

    Flexible coaxial cables were modified to serve as microwave antennas operating at a frequency of 915 MHz. These antennas were inserted into nylon afterloading tubes that had been implanted in tumors using conventional interstitial implantation techniques for iridium-192 seed brachytherapy. The tumor volume was heated to 42-45 degrees C within 15 minutes and heating was continued for a total of 1 hour per treatment. Immediately following a conventional brachytherapy dose and removal of the iridium seeds the tumors were heated again in a second treatment. This interstitial technique for delivering local hyperthermia should be compatible with most brachytherapy methods. The technique has proved so far to be practical and without complications. Temperature distributions obtained in tissue phantoms and a patient are described.

  17. Outpatient vaginal cuff brachytherapy for endometrial cancer.

    PubMed

    Petereit, D. G.; Tannehill, S. P.; Grosen, E. A.; Hartenbach, E. M.; Schink, J. C.

    1999-11-01

    Petereit DG, Tannehill SP, Grosen EA, Hartenbach EM, Schink JC. Outpatient vaginal cuff brachytherapy for endometrial cancer. The objective of this study was to determine the efficacy and complications of postoperative high-dose-rate (HDR) vaginal-cuff brachytherapy (VCB) in patients with endometrial carcinoma. Between August 1989 to September 1997, 191 patients were treated postoperatively after a total abdominal hysterectomy and bilateral salpingo-oophorectomy (TAH/BSO) with outpatient adjuvant HDR VCB for low-risk endometrial cancer (IB-84%, grade 1 or 2-96%). Patients were treated with 2 HDR fractions, delivered one week apart while under conscious sedation (16.2 Gy X 2 to the vaginal surface). All clinical endpoints were calculated using the Kaplan Meier method. The median time in the brachytherapy suite was 60 min in which no acute complications were observed. The 30-day morbidity and mortality rates were both 0%. With a median follow-up of 38 months (12-82 months), the 4-year survival, relapse-free survival, and vaginal-control rates were 95%, 98%, and 100%, respectively. One patient developed a colo-vaginal fistula at 5 years. Adjuvant HDR VCB in 2 outpatient insertions produced 100% vaginal control rates with minimal morbidity. The advantages of high dose-rate compared to low dose-rate vaginal brachytherapy include patient convenience, markedly shorter treatment times (1 h per insertion), and reduction in the cost and potential morbidity of hospitalization. HDR brachytherapy approach is a cost-effective alternative to either low-dose-rate brachytherapy or whole pelvic radiotherapy in carefully selected patients.

  18. Permanent Contraception for Women.

    PubMed

    Patil, Eva; Jensen, Jeffrey T

    2016-05-01

    Permanent contraception is a highly desired and commonly used contraceptive option for women around the world who desire never to become pregnant. Current methods of female permanent contraception require surgery. Postpartum tubal ligation and interval surgical tubal ligation are safe and effective, do not interfere with menstrual cycles, and require no ongoing cost or medical checkups. Hysteroscopic tubal occlusion offers a less invasive surgical approach, but requires an imaging study for verification of correct placement. However, not all women have access to a surgeon trained to provide permanent contraception, or they may face other prohibitive logistic or financial burdens. The development of novel permanent contraception methods that are immediately effective and/or nonsurgical could help improve access to and acceptability of permanent contraception. The expansion of permanent contraception options could help women achieve their family planning goals and reduce unintended pregnancies.

  19. Overview: Five decades of brachytherapy

    SciTech Connect

    Ellis, F.

    1986-01-01

    Brachytherapy started in 1930. Ra-226 was the radioisotope for cancer therapy at that time and much has been learned about its properties since then. One of the major findings at that time was output. When the author started, there was no T factor. People did not know how many R units were produced by 1.0 mg of radium filtered by 0.5 mm of platinum at 1.0 cm. So one was in a bit of chaos from that point of view. Eventually, that was settled in the 1930's. It was very exciting to find out that, although the national laboratories of the U.S., England, France and Germany had had values of this T factor varying from about five to seven (when they're only supposed to have less than 1% error); the value was really 8.3 and it was quite a landmark. This led to an improved knowledge of dose and effects. Developments over the next five decades are discussed in detail.

  20. Oscillating Permanent Magnets.

    ERIC Educational Resources Information Center

    Michaelis, M. M.; Haines, C. M.

    1989-01-01

    Describes several ways to partially levitate permanent magnets. Computes field line geometries and oscillation frequencies. Provides several diagrams illustrating the mechanism of the oscillation. (YP)

  1. Patterns of care study for brachytherapy: results of the questionnaire for the years 2002 and 2007 in The Netherlands

    PubMed Central

    Slotman, Ben J.; Guedea, Ferran; Ventura, Montse; Londres, Bradley; Francois, Guy

    2011-01-01

    Purpose The goal of the ESTRO Patterns of Care study for Brachytherapy in Europe (PCBE) 2002 was to develop an aid to analyse brachytherapy practices. A 2nd version of the PCB questionnaire was created for 2007. Data over 2007 were collected at the radiotherapy institutions in The Netherlands and compared with those from 2002. The aim of this study is to describe national brachytherapy practices, to demonstrate trends, and to provide data for rational health care planning. Material and methods Data were collected using a web-based questionnaire. For each centre, a local coordinator, responsible for coordinating the questionnaires and support of the further analysis was assigned. Data from the national cancer incidence registry was used for comparison with the data from the 21 Dutch departments. Results There was a decrease in low-dose rate equipment in parallel to an increase in both pulsed-dose rate and high-dose rate equipment. The use of 3D CT and MR based imaging techniques showed a slow rise. The most common clinical procedures were for prostate, gynaecological, and oesophageal tumours. A large increase (146%) in permanent implant prostate applications using 125I seeds was observed. The numbers of oesophageal and gynaecological treatments remained stable. There is concern on the low numbers of cases treated in some institutions for a few complex treatment sites. For head and neck, anal canal, paediatrics, bladder and eye interventions it ranged from 3-20 patients per year per institution. Conclusions The increase in number of patient treated with brachytherapy is in accordance with the increases in cancer incidence. The percentage of all radiotherapy patients treated with brachytherapy (approximately 5%) remained stable. The survey identified certain trends in resources and techniques, as well as areas of expected improvement and possible gain in clinical outcome. Data reported from this survey can be used for further planning of resources, facilities and

  2. Comparison of High-Dose Proton Radiotherapy and Brachytherapy in Localized Prostate Cancer: A Case-Matched Analysis

    SciTech Connect

    Coen, John J.; Zietman, Anthony L.; Rossi, Carl J.; Grocela, Joseph A.; Efstathiou, Jason A.; Yan, Yan; Shipley, William U.

    2012-01-01

    Purpose: To report a case-matched analysis comparing high-dose external-beam radiation (EBRT) for prostate cancer delivered on Proton Radiation Oncology Group (PROG) 95-09, a randomized trial, with permanent prostate brachytherapy over the same era. Methods: From 1996 to 1999, 196 patients were accrued to the high-dose arm (79.2 Gray equivalent (GyE) using photons and protons) of PROG 95-09 at the Massachusetts General Hospital and Loma Linda University Medical Center. Entry criteria specified T1-2 and prostate-specific antigen {<=}15 ng/mL. When Gleason score >7 was excluded, 177 men were left for case matching. At Massachusetts General Hospital, 203 similar patients were treated by a single brachytherapist from 1997 to 2002. Minimum follow-up was 3 years. Case matching, based on T stage, Gleason score, prostate-specific antigen, and age resulted in 141 matches (282 patients). Median follow-up was 8.6 and 7.4 years for EBRT and brachytherapy, respectively. The primary endpoint was biochemical failure (BF). Results: Using the Phoenix definition, the 8-year BF rates were 7.7% and 16.1% for EBRT and brachytherapy, respectively (p = 0.42). A stratified analysis was performed by risk group. In the EBRT group, 113 and 28 patients were low and intermediate risk, respectively. In the brachytherapy group, 118 and 23 were. When stratified by risk group, the BF rates were similar by either technique. Conclusions: High-dose EBRT and brachytherapy result in similar BF rates for men with localized prostate cancer. Comparative quality-of-life and cost-effectiveness studies are warranted.

  3. Permanent magnet assembly

    DOEpatents

    Chell, Jeremy; Zimm, Carl B.

    2006-12-12

    A permanent magnet assembly is disclosed that is adapted to provide a magnetic field across an arc-shaped gap. Such a permanent magnet assembly can be used, for example, to provide a time-varying magnetic field to an annular region for use in a magnetic refrigerator.

  4. Permanent tensions in organization.

    PubMed

    Jansson, Noora

    2015-01-01

    The purpose of this paper is to investigate the relationship between permanent tensions and organizational change. This study used paradox theory and a case study. The case organization is a public university hospital in Finland involving several stakeholders. The analysis suggests that the relationship between permanent tensions and organizational change is a paradox that is part of organizational reality. As an organization learns to live with its permanent tensions, the renewal paradox settles into equilibrium. When tensions are provoked, the paradox is disturbed until it finds a new balance. This flexible nature of the paradox is the force that keeps the different stakeholders simultaneously empowered to maintain their unique missions and cohesive in order to benefit from the larger synergy. This research suggests that identification and evaluation of each permanent tension within an organization is important when executing organizational change. The fact that certain tensions are permanent and cannot be solved may have an influence on how planned change initiatives are executed. The results show that permanent tensions may be harnessed for the benefit of an organizational change. This research demonstrates originality by offering an alternative view of tensions, a view which emphasizes not only their permanent and plural nature but their importance for enabling the organization to change at its own, non-disruptive pace. The research also proposes a new concept, the "renewal paradox", to enhance understanding of the relationship between permanent tensions and organizational change.

  5. The American Brachytherapy Society Treatment Recommendations for Locally Advanced Carcinoma of the Cervix Part II: High Dose-Rate Brachytherapy

    PubMed Central

    Viswanathan, Akila N.; Beriwal, Sushil; De Los Santos, Jennifer; Demanes, D. Jeffrey; Gaffney, David; Hansen, Jorgen; Jones, Ellen; Kirisits, Christian; Thomadsen, Bruce; Erickson, Beth

    2012-01-01

    Purpose This report presents the 2011 update to the American Brachytherapy Society (ABS) high-dose-rate (HDR) brachytherapy guidelines for locally advanced cervical cancer. Methods Members of the American Brachytherapy Society (ABS) with expertise in cervical cancer brachytherapy formulated updated guidelines for HDR brachytherapy using tandem and ring, ovoids, cylinder or interstitial applicators for locally advanced cervical cancer were revised based on medical evidence in the literature and input of clinical experts in gynecologic brachytherapy. Results The Cervical Cancer Committee for Guideline Development affirms the essential curative role of tandem-based brachytherapy in the management of locally advanced cervical cancer. Proper applicator selection, insertion, and imaging are fundamental aspects of the procedure. Three-dimensional imaging with magnetic resonance or computed tomography or radiographic imaging may be used for treatment planning. Dosimetry must be performed after each insertion prior to treatment delivery. Applicator placement, dose specification and dose fractionation must be documented, quality assurance measures must be performed, and follow-up information must be obtained. A variety of dose/fractionation schedules and methods for integrating brachytherapy with external-beam radiation exist. The recommended tumor dose in 2 Gray (Gy) per fraction radiobiologic equivalence (EQD2) is 80–90 Gy, depending on tumor size at the time of brachytherapy. Dose limits for normal tissues are discussed. Conclusion These guidelines update those of 2000 and provide a comprehensive description of HDR cervical cancer brachytherapy in 2011. PMID:22265437

  6. Evaluation of brachytherapy lung implant dose distributions from photon-emitting sources due to tissue heterogeneities.

    PubMed

    Yang, Yun; Rivard, Mark J

    2011-11-01

    Photon-emitting brachytherapy sources are used for permanent implantation to treat lung cancer. However, the current brachytherapy dose calculation formalism assumes a homogeneous water medium without considering the influence of radiation scatter or tissue heterogeneities. The purpose of this study was to determine the dosimetric effects of tissue heterogeneities for permanent lung brachytherapy. The MCNP5 v1.40 radiation transport code was used for Monte Carlo (MC) simulations. Point sources with energies of 0.02, 0.03, 0.05, 0.1, 0.2, and 0.4 MeV were simulated to cover the range of pertinent brachytherapy energies and to glean dosimetric trends independent of specific radionuclide emissions. Source positions from postimplant CT scans of five patient implants were used for source coordinates, with dose normalized to 200 Gy at the center of each implant. With the presence of fibrosis (around the implant), cortical bone, lung, and healthy tissues, dose distributions and (PTV)DVH were calculated using the MCNP ∗FMESH4 tally and the NIST mass-energy absorption coefficients. This process was repeated upon replacing all tissues with water. For all photon energies, 10(9) histories were simulated to achieve statistical errors (k = 1) typically of 1%. The mean PTV doses calculated using tissue heterogeneities for all five patients changed (compared to dose to water) by only a few percent over the examined photon energy range, as did PTV dose at the implant center. The (PTV)V(100) values were 81.2%, 90.0% (as normalized), 94.3%, 93.9%, 92.7%, and 92.2% for 0.02, 0.03, 0.05, 0.1, 0.2, and 0.4 MeV source photons, respectively. Relative to water, the maximum bone doses were higher by factors of 3.7, 5.1, 5.2, 2.4, 1.2, and 1.0 The maximum lung doses were about 0.98, 0.94, 0.91, 0.94, 0.97, and 0.99. Relative to water, the maximum healthy tissue doses at the mediastinal position were higher by factors of 9.8, 2.2, 1.3, 1.1, 1.1, and 1.1. However, the maximum doses to

  7. Evaluation of brachytherapy lung implant dose distributions from photon-emitting sources due to tissue heterogeneities

    SciTech Connect

    Yang Yun; Rivard, Mark J.

    2011-11-15

    Purpose: Photon-emitting brachytherapy sources are used for permanent implantation to treat lung cancer. However, the current brachytherapy dose calculation formalism assumes a homogeneous water medium without considering the influence of radiation scatter or tissue heterogeneities. The purpose of this study was to determine the dosimetric effects of tissue heterogeneities for permanent lung brachytherapy. Methods: The MCNP5 v1.40 radiation transport code was used for Monte Carlo (MC) simulations. Point sources with energies of 0.02, 0.03, 0.05, 0.1, 0.2, and 0.4 MeV were simulated to cover the range of pertinent brachytherapy energies and to glean dosimetric trends independent of specific radionuclide emissions. Source positions from postimplant CT scans of five patient implants were used for source coordinates, with dose normalized to 200 Gy at the center of each implant. With the presence of fibrosis (around the implant), cortical bone, lung, and healthy tissues, dose distributions and {sub PTV}DVH were calculated using the MCNP *FMESH4 tally and the NIST mass-energy absorption coefficients. This process was repeated upon replacing all tissues with water. For all photon energies, 10{sup 9} histories were simulated to achieve statistical errors (k = 1) typically of 1%. Results: The mean PTV doses calculated using tissue heterogeneities for all five patients changed (compared to dose to water) by only a few percent over the examined photon energy range, as did PTV dose at the implant center. The {sub PTV}V{sub 100} values were 81.2%, 90.0% (as normalized), 94.3%, 93.9%, 92.7%, and 92.2% for 0.02, 0.03, 0.05, 0.1, 0.2, and 0.4 MeV source photons, respectively. Relative to water, the maximum bone doses were higher by factors of 3.7, 5.1, 5.2, 2.4, 1.2, and 1.0 The maximum lung doses were about 0.98, 0.94, 0.91, 0.94, 0.97, and 0.99. Relative to water, the maximum healthy tissue doses at the mediastinal position were higher by factors of 9.8, 2.2, 1.3, 1.1, 1.1, and

  8. MO-D-BRD-00: Electronic Brachytherapy

    SciTech Connect

    2015-06-15

    Electronic brachytherapy (eBT) has seen an insurgence of manufacturers entering the US market for use in radiation therapy. In addition to the established interstitial, intraluminary, and intracavitary applications of eBT, many centers are now using eBT to treat skin lesions. It is important for medical physicists working with electronic brachytherapy sources to understand the basic physics principles of the sources themselves as well as the variety of applications for which they are being used. The calibration of the sources is different from vendor to vendor and the traceability of calibrations has evolved as new sources came to market. In 2014, a new air-kerma based standard was introduced by the National Institute of Standards and Technology (NIST) to measure the output of an eBT source. Eventually commercial treatment planning systems should accommodate this new standard and provide NIST traceability to the end user. The calibration and commissioning of an eBT system is unique to its application and typically entails a list of procedural recommendations by the manufacturer. Commissioning measurements are performed using a variety of methods, some of which are modifications of existing AAPM Task Group protocols. A medical physicist should be familiar with the different AAPM Task Group recommendations for applicability to eBT and how to properly adapt them to their needs. In addition to the physical characteristics of an eBT source, the photon energy is substantially lower than from HDR Ir-192 sources. Consequently, tissue-specific dosimetry and radiobiological considerations are necessary when comparing these brachytherapy modalities and when making clinical decisions as a radiation therapy team. In this session, the physical characteristics and calibration methodologies of eBt sources will be presented as well as radiobiology considerations and other important clinical considerations. Learning Objectives: To understand the basic principles of electronic

  9. Automated intraoperative calibration for prostate cancer brachytherapy

    SciTech Connect

    Kuiran Chen, Thomas; Heffter, Tamas; Lasso, Andras; Pinter, Csaba; Abolmaesumi, Purang; Burdette, E. Clif; Fichtinger, Gabor

    2011-11-15

    Purpose: Prostate cancer brachytherapy relies on an accurate spatial registration between the implant needles and the TRUS image, called ''calibration''. The authors propose a new device and a fast, automatic method to calibrate the brachytherapy system in the operating room, with instant error feedback. Methods: A device was CAD-designed and precision-engineered, which mechanically couples a calibration phantom with an exact replica of the standard brachytherapy template. From real-time TRUS images acquired from the calibration device and processed by the calibration system, the coordinate transformation between the brachytherapy template and the TRUS images was computed automatically. The system instantly generated a report of the target reconstruction accuracy based on the current calibration outcome. Results: Four types of validation tests were conducted. First, 50 independent, real-time calibration trials yielded an average of 0.57 {+-} 0.13 mm line reconstruction error (LRE) relative to ground truth. Second, the averaged LRE was 0.37 {+-} 0.25 mm relative to ground truth in tests with six different commercial TRUS scanners operating at similar imaging settings. Furthermore, testing with five different commercial stepper systems yielded an average of 0.29 {+-} 0.16 mm LRE relative to ground truth. Finally, the system achieved an average of 0.56 {+-} 0.27 mm target registration error (TRE) relative to ground truth in needle insertion tests through the template in a water tank. Conclusions: The proposed automatic, intraoperative calibration system for prostate cancer brachytherapy has achieved high accuracy, precision, and robustness.

  10. State-of-the-art: prostate LDR brachytherapy.

    PubMed

    Voulgaris, S; Nobes, J P; Laing, R W; Langley, S E M

    2008-01-01

    This article on low dose rate (LDR) prostate brachytherapy reviews long-term results, patient selection and quality of life issues. Mature results from the United States and United Kingdom are reported and issues regarding definitions of biochemical failure are discussed. Latest data comparing brachytherapy with radical prostatectomy or no definitive treatment and also the risk of secondary malignancies after prostate brachytherapy are presented. Urological parameters of patient selection and quality of life issues concerning urinary, sexual and bowel function are reviewed. The position of prostate brachytherapy next to surgery as a first-line treatment modality is demonstrated.

  11. Study of Dosimetric and Thermal Properties of a Newly Developed Thermo-brachytherapy Seed for Treatment of Solid Tumors

    NASA Astrophysics Data System (ADS)

    Gautam, Bhoj R.

    Studies on the curative effects of hyperthermia and radiation therapy on treatment of cancer show strong evidence of synergistic enhancement when both radiation and hyperthermia treatment modalities are applied simultaneously. A variety of tissue heating approaches developed to date still fail to overcome essential limitations such as inadequate temperature control, temperature non-uniformity, and prolonged time delay between hyperthermia and radiation treatments. We propose a new self-regulating Thermo-brachytherapy (TB) seed, which serves as a source of both radiation and heat for concurrent administration of brachytherapy and hyperthermia. The proposed seed is based on the BestRTM Iodine-125 seed model 2301, where the tungsten marker core and the air gap are replaced with ferromagnetic material. The ferromagnetic core produces heat when subjected to an alternating electromagnetic (EM) field and effectively shuts off after reaching the Curie temperature (TC) of the ferromagnetic material, thus establishing temperature self-regulation. The seed has a ferromagnetic Ni-Cu alloy core having a Curie transition at a temperature of 52 °C. This study summarizes the design and development of the self regulating ferromagnetic core TB seed for the concurrent hyperthermia and brachytherapy treatments. An experimental study of the magnetic properties of the Ni1-xCu x (0.28≤ x ≤0.3) alloys, and the simulation studies of radiation and thermal distribution properties of the seed have been performed. A preliminary experiment for the ferromagnetic induction heating of Ni-Cu needles has been carried out to ensure the practical feasibility of the induction heating. Radiation dose characterizing parameters (dose rate constant and other TG-43 factors) were calculated using the Monte Carlo method. For the thermal characteristics, we studied a model consisting of single or multiple seeds placed in the central region of a cylindrical phantom using a finite-element analysis method

  12. 10 CFR 35.400 - Use of sources for manual brachytherapy.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Use of sources for manual brachytherapy. 35.400 Section 35.400 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35.400 Use of sources for manual brachytherapy. A licensee shall use only brachytherapy sources...

  13. 10 CFR 35.400 - Use of sources for manual brachytherapy.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Use of sources for manual brachytherapy. 35.400 Section 35.400 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35.400 Use of sources for manual brachytherapy. A licensee shall use only brachytherapy sources...

  14. 10 CFR 35.400 - Use of sources for manual brachytherapy.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Use of sources for manual brachytherapy. 35.400 Section 35.400 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35.400 Use of sources for manual brachytherapy. A licensee shall use only brachytherapy sources...

  15. 10 CFR 35.400 - Use of sources for manual brachytherapy.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Use of sources for manual brachytherapy. 35.400 Section 35.400 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy § 35.400 Use of sources for manual brachytherapy. A licensee shall use only brachytherapy sources...

  16. Modern head and neck brachytherapy: from radium towards intensity modulated interventional brachytherapy

    PubMed Central

    2014-01-01

    Intensity modulated brachytherapy (IMBT) is a modern development of classical interventional radiation therapy (brachytherapy), which allows the application of a high radiation dose sparing severe adverse events, thereby further improving the treatment outcome. Classical indications in head and neck (H&N) cancers are the face, the oral cavity, the naso- and oropharynx, the paranasal sinuses including base of skull, incomplete resections on important structures, and palliation. The application type can be curative, adjuvant or perioperative, as a boost to external beam radiation as well as without external beam radiation and with palliative intention. Due to the frequently used perioperative application method (intraoperative implantation of inactive applicators and postoperative performance of radiation), close interdisciplinary cooperation between surgical specialists (ENT-, dento-maxillary-facial-, neuro- and orbital surgeons), as well interventional radiotherapy (brachytherapy) experts are obligatory. Published results encourage the integration of IMBT into H&N therapy, thereby improving the prognosis and quality of life of patients. PMID:25834586

  17. Physics and basic parameters of brachytherapy.

    PubMed

    Lee, E J; Weinhous, M S

    1997-06-01

    Brachytherapy (short-distance therapy) is the therapeutic process whereby radioactive sources are placed into very close proximity to target tissue. Radioactive materials were so used beginning shortly after the discovery of radium by Marie and Pierre Curie in 1898. For the purposes of brachytherapy, radioactive materials are those that emit "rays" that can cause ionization (and hence DNA damage and the destruction of target cells). The potentially useful rays include beta, gamma, and other possibilities such as neutrons. Beta rays, properly beta particles, are simply high energy electrons. Gamma rays are high energy photons (part of the electromagnetic spectrum like visible light, but with much higher energy). These particles are produced during the radioactive decay of certain isotopes. The physics of those events and the parameters that apply to the therapeutic use of the isotopes are the primary topics of this report.

  18. PSA Bounce and Biochemical Failure After Brachytherapy for Prostate Cancer: A Study of 820 Patients With a Minimum of 3 Years of Follow-Up

    SciTech Connect

    Caloglu, Murat; Ciezki, Jay P.; Reddy, Chandana A.; Angermeier, Kenneth; Ulchaker, James; Chehade, Nabil; Altman, Andrew; Magi-Galuzzi, Christina; Klein, Eric A.

    2011-07-01

    Purpose: To determine clinical or dosimetric factors associated with a prostate-specific antigen (PSA) bounce, as well as an association between a PSA bounce and biochemical relapse-free survival (bRFS), in patients treated with iodine-125 brachytherapy. Methods and Materials: A variety of clinical and treatment factors were examined in 820 patients who had a minimum of 3 years of PSA follow-up with T1-T2cN0M0 prostate cancer. Four different PSA threshold values were used for defining a PSA bounce: a PSA rise of {>=}0.2, {>=}0.4, {>=}0.6, and {>=}0.8 ng/mL. Results: A PSA bounce of {>=}0.2, {>=}0.4, {>=}0.6, and {>=}0.8 ng/mL was noted in 247 patients (30.1%), 161 (19.6%), 105 (12.8%), and 78 (9.5%), respectively. The median time to the first PSA rise was 17.4, 16.25, 16.23, and 15.71 months, respectively, vs. 34.35 months for a biochemical failure (p < 0.0001). A PSA rise of {>=}0.2 ng/mL was the only definition for which there was a significant difference in bRFS between bounce and non-bounce patients. The 5-year bRFS rate of patients having a PSA bounce of {>=}0.2 was 97.7% vs. 91% for those who did not have a PSA bounce (p = 0.0011). On univariate analysis for biochemical failure, age, risk group, and PSAs per year had a statistically significant correlation with PSA bounce of {>=}0.2 ng/mL. On multivariate analysis, age and PSAs per year remained statistically significant (p < 0.0001 and p = 0.0456, respectively). Conclusions: A bounce definition of a rise {>=}0.2 ng/mL is a reliable definition among several other definitions. The time to first PSA rise is the most valuable factor for distinguishing between a bounce and biochemical failure.

  19. Design and optimization of a brachytherapy robot

    NASA Astrophysics Data System (ADS)

    Meltsner, Michael A.

    Trans-rectal ultrasound guided (TRUS) low dose rate (LDR) interstitial brachytherapy has become a popular procedure for the treatment of prostate cancer, the most common type of non-skin cancer among men. The current TRUS technique of LDR implantation may result in less than ideal coverage of the tumor with increased risk of negative response such as rectal toxicity and urinary retention. This technique is limited by the skill of the physician performing the implant, the accuracy of needle localization, and the inherent weaknesses of the procedure itself. The treatment may require 100 or more sources and 25 needles, compounding the inaccuracy of the needle localization procedure. A robot designed for prostate brachytherapy may increase the accuracy of needle placement while minimizing the effect of physician technique in the TRUS procedure. Furthermore, a robot may improve associated toxicities by utilizing angled insertions and freeing implantations from constraints applied by the 0.5 cm-spaced template used in the TRUS method. Within our group, Lin et al. have designed a new type of LDR source. The "directional" source is a seed designed to be partially shielded. Thus, a directional, or anisotropic, source does not emit radiation in all directions. The source can be oriented to irradiate cancerous tissues while sparing normal ones. This type of source necessitates a new, highly accurate method for localization in 6 degrees of freedom. A robot is the best way to accomplish this task accurately. The following presentation of work describes the invention and optimization of a new prostate brachytherapy robot that fulfills these goals. Furthermore, some research has been dedicated to the use of the robot to perform needle insertion tasks (brachytherapy, biopsy, RF ablation, etc.) in nearly any other soft tissue in the body. This can be accomplished with the robot combined with automatic, magnetic tracking.

  20. Development of a brachytherapy audit checklist tool.

    PubMed

    Prisciandaro, Joann; Hadley, Scott; Jolly, Shruti; Lee, Choonik; Roberson, Peter; Roberts, Donald; Ritter, Timothy

    2015-01-01

    To develop a brachytherapy audit checklist that could be used to prepare for Nuclear Regulatory Commission or agreement state inspections, to aid in readiness for a practice accreditation visit, or to be used as an annual internal audit tool. Six board-certified medical physicists and one radiation oncologist conducted a thorough review of brachytherapy-related literature and practice guidelines published by professional organizations and federal regulations. The team members worked at two facilities that are part of a large, academic health care center. Checklist items were given a score based on their judged importance. Four clinical sites performed an audit of their program using the checklist. The sites were asked to score each item based on a defined severity scale for their noncompliance, and final audit scores were tallied by summing the products of importance score and severity score for each item. The final audit checklist, which is available online, contains 83 items. The audit scores from the beta sites ranged from 17 to 71 (out of 690) and identified a total of 7-16 noncompliance items. The total time to conduct the audit ranged from 1.5 to 5 hours. A comprehensive audit checklist was developed which can be implemented by any facility that wishes to perform a program audit in support of their own brachytherapy program. The checklist is designed to allow users to identify areas of noncompliance and to prioritize how these items are addressed to minimize deviations from nationally-recognized standards. Copyright © 2015 American Brachytherapy Society. All rights reserved.

  1. Rotating-shield brachytherapy for cervical cancer

    NASA Astrophysics Data System (ADS)

    Yang, Wenjun; Kim, Yusung; Wu, Xiaodong; Song, Qi; Liu, Yunlong; Bhatia, Sudershan K.; Sun, Wenqing; Flynn, Ryan T.

    2013-06-01

    In this treatment planning study, the potential benefits of a rotating shield brachytherapy (RSBT) technique based on a partially-shielded electronic brachytherapy source were assessed for treating cervical cancer. Conventional intracavitary brachytherapy (ICBT), intracavitary plus supplementary interstitial (IS+ICBT), and RSBT treatment plans for azimuthal emission angles of 180° (RSBT-180) and 45° (RSBT-45) were generated for five patients. For each patient, high-risk clinical target volume (HR-CTV) equivalent dose in 2 Gy fractions (EQD2) (α/β = 10 Gy) was escalated until bladder, rectum, or sigmoid colon tolerance EQD2 values were reached. External beam radiotherapy dose (1.8 Gy × 25) was accounted for, and brachytherapy was assumed to have been delivered in 5 fractions. IS+ICBT provided a greater HR-CTV D90 (minimum EQD2 to the hottest 90%) than ICBT. D90 was greater for RSBT-45 than IS+ICBT for all five patients, and greater for RSBT-180 than IS+ICBT for two patients. When the RSBT-45/180 plan with the lowest HR-CTV D90 that was greater than the D90 the ICBT or IS+ICBT plan was selected, the average (range) of D90 increases for RSBT over ICBT and IS+ICBT were 16.2 (6.3-27.2)and 8.5 (0.03-20.16) Gy, respectively. The average (range) treatment time increase per fraction of RSBT was 34.56 (3.68-70.41) min over ICBT and 34.59 (3.57-70.13) min over IS+ICBT. RSBT can increase D90 over ICBT and IS+ICBT without compromising organ-at-risk sparing. The D90 and treatment time improvements from RSBT depend on the patient and shield emission angle.

  2. Sensitivity of low energy brachytherapy Monte Carlo dose calculations to uncertainties in human tissue composition

    SciTech Connect

    Landry, Guillaume; Reniers, Brigitte; Murrer, Lars; Lutgens, Ludy; Bloemen-Van Gurp, Esther; Pignol, Jean-Philippe; Keller, Brian; Beaulieu, Luc; Verhaegen, Frank

    2010-10-15

    Purpose: The objective of this work is to assess the sensitivity of Monte Carlo (MC) dose calculations to uncertainties in human tissue composition for a range of low photon energy brachytherapy sources: {sup 125}I, {sup 103}Pd, {sup 131}Cs, and an electronic brachytherapy source (EBS). The low energy photons emitted by these sources make the dosimetry sensitive to variations in tissue atomic number due to the dominance of the photoelectric effect. This work reports dose to a small mass of water in medium D{sub w,m} as opposed to dose to a small mass of medium in medium D{sub m,m}. Methods: Mean adipose, mammary gland, and breast tissues (as uniform mixture of the aforementioned tissues) are investigated as well as compositions corresponding to one standard deviation from the mean. Prostate mean compositions from three different literature sources are also investigated. Three sets of MC simulations are performed with the GEANT4 code: (1) Dose calculations for idealized TG-43-like spherical geometries using point sources. Radial dose profiles obtained in different media are compared to assess the influence of compositional uncertainties. (2) Dose calculations for four clinical prostate LDR brachytherapy permanent seed implants using {sup 125}I seeds (Model 2301, Best Medical, Springfield, VA). The effect of varying the prostate composition in the planning target volume (PTV) is investigated by comparing PTV D{sub 90} values. (3) Dose calculations for four clinical breast LDR brachytherapy permanent seed implants using {sup 103}Pd seeds (Model 2335, Best Medical). The effects of varying the adipose/gland ratio in the PTV and of varying the elemental composition of adipose and gland within one standard deviation of the assumed mean composition are investigated by comparing PTV D{sub 90} values. For (2) and (3), the influence of using the mass density from CT scans instead of unit mass density is also assessed. Results: Results from simulation (1) show that variations

  3. Sensitivity of low energy brachytherapy Monte Carlo dose calculations to uncertainties in human tissue composition.

    PubMed

    Landry, Guillaume; Reniers, Brigitte; Murrer, Lars; Lutgens, Ludy; Gurp, Esther Bloemen-Van; Pignol, Jean-Philippe; Keller, Brian; Beaulieu, Luc; Verhaegen, Frank

    2010-10-01

    The objective of this work is to assess the sensitivity of Monte Carlo (MC) dose calculations to uncertainties in human tissue composition for a range of low photon energy brachytherapy sources: 125I, 103Pd, 131Cs, and an electronic brachytherapy source (EBS). The low energy photons emitted by these sources make the dosimetry sensitive to variations in tissue atomic number due to the dominance of the photoelectric effect. This work reports dose to a small mass of water in medium D(w,m) as opposed to dose to a small mass of medium in medium D(m,m). Mean adipose, mammary gland, and breast tissues (as uniform mixture of the aforementioned tissues) are investigated as well as compositions corresponding to one standard deviation from the mean. Prostate mean compositions from three different literature sources are also investigated. Three sets of MC simulations are performed with the GEANT4 code: (1) Dose calculations for idealized TG-43-like spherical geometries using point sources. Radial dose profiles obtained in different media are compared to assess the influence of compositional uncertainties. (2) Dose calculations for four clinical prostate LDR brachytherapy permanent seed implants using 125I seeds (Model 2301, Best Medical, Springfield, VA). The effect of varying the prostate composition in the planning target volume (PTV) is investigated by comparing PTV D90 values. (3) Dose calculations for four clinical breast LDR brachytherapy permanent seed implants using 103Pd seeds (Model 2335, Best Medical). The effects of varying the adipose/gland ratio in the PTV and of varying the elemental composition of adipose and gland within one standard deviation of the assumed mean composition are investigated by comparing PTV D90 values. For (2) and (3), the influence of using the mass density from CT scans instead of unit mass density is also assessed. Results from simulation (1) show that variations in the mean compositions of tissues affect low energy brachytherapy dosimetry

  4. An Active Mammosite For Breast Brachytherapy

    NASA Astrophysics Data System (ADS)

    Cudjoe, Thomas

    2006-03-01

    Brachytherapy is an advanced cancer treatment that uses radioactive sources inside or in close proximity to cancerous tumors, thus minimizing exposure to neighboring healthy cells. This radiation oncology treatment unlike many others is localized and precise. The latest involvement of the Brachytherapy research group of the medical physics program at Hampton University is in the development of a scintillator fiber based detector for the breast cancer specific Mammosite (balloon device) from Cytyc Inc. Radioactive sources are inserted into a small plastic catheter (shaft) and pushed at the end of the tube. At that location, a water filled balloon surrounds the source and allow uniform gamma emission into cancer tumors. There is presently no capability for this device to provide measurements of the location of the source, as well as the radiation emitted from the source. Recent data were acquired to evaluate the possibility of measuring the dose distribution during breast Brachytherapy cancer treatments with this device. A high activity ^192Ir radioactive source and a 0.5 and 1 mm^2 scintillating fibers were used. Results will be presented and discussed.

  5. Brachytherapy for the treatment of prostate cancer.

    PubMed

    Cesaretti, Jamie A; Stone, Nelson N; Skouteris, Vassilios M; Park, Janelle L; Stock, Richard G

    2007-01-01

    Low-dose rate brachytherapy has become a mainstream treatment option for men diagnosed with prostate cancer because of excellent long-term treatment outcomes in low-, intermediate-, and high-risk patients. Largely due to patient lead advocacy for minimally invasive treatment options, high-quality prostate implants have become widely available in the US, Europe, and Japan. The reason that brachytherapy results are reproducible in several different practice settings is because numerous implant quality factors have been defined over the last 20 years, which can be applied objectively to judge the success of the intervention both during and after the procedure. In addition, recent long-term follow-up studies have clarified that the secondary cancer incidence of brachytherapy is not clinically meaningful. In terms of future directions, the study of radiation repair genetics may allow for the counseling physician to better estimate any given patients risk for side effects, thereby substantially reducing the therapeutic uncertainties faced by patients choosing a prostate cancer intervention.

  6. 10 CFR 35.432 - Calibration measurements of brachytherapy sources.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Calibration measurements of brachytherapy sources. 35.432 Section 35.432 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy... Association of Physicists in Medicine that are made in accordance with paragraph (a) of this section. (c)...

  7. 10 CFR 35.432 - Calibration measurements of brachytherapy sources.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Calibration measurements of brachytherapy sources. 35.432 Section 35.432 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy... Association of Physicists in Medicine that are made in accordance with paragraph (a) of this section. (c)...

  8. 10 CFR 35.432 - Calibration measurements of brachytherapy sources.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 1 2012-01-01 2012-01-01 false Calibration measurements of brachytherapy sources. 35.432 Section 35.432 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy... Association of Physicists in Medicine that are made in accordance with paragraph (a) of this section. (c)...

  9. 10 CFR 35.432 - Calibration measurements of brachytherapy sources.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Calibration measurements of brachytherapy sources. 35.432 Section 35.432 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy... Association of Physicists in Medicine that are made in accordance with paragraph (a) of this section. (c)...

  10. 10 CFR 35.432 - Calibration measurements of brachytherapy sources.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Calibration measurements of brachytherapy sources. 35.432 Section 35.432 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Manual Brachytherapy... Association of Physicists in Medicine that are made in accordance with paragraph (a) of this section. (c)...

  11. Current status and perspectives of brachytherapy for breast cancer.

    PubMed

    Polgár, Csaba; Major, Tibor

    2009-02-01

    Before the era of breast-conserving therapy, brachytherapy implants were used to treat large inoperable breast tumors. In later years, interstitial brachytherapy with rigid needles or multiple flexible catheters has been used to deliver an additional (boost) dose to the tumor bed after breast-conserving surgery and whole-breast irradiation. Reexcision followed by reirradiation using interstitial breast implants has also been implemented as an alternative to mastectomy to treat ipsilateral breast local recurrence after previous breast-conserving therapy. In the past two decades, the new concept of accelerated partial breast irradiation opened a new perspective for breast brachytherapy. The first technique utilized in early accelerated partial breast irradiation studies was multicatheter interstitial brachytherapy. Beyond classical interstitial brachytherapy, recently, new intracavitary applicators have been developed in the United States to decrease the existing barriers against the widespread use of multicatheter brachytherapy. Furthermore, interstitial low-dose-rate seed implants have also been implemented as an alternative for stepping-source multicatheter brachytherapy. In this article, we give an overview of the past achievements, current status, and future perspectives of breast brachytherapy.

  12. 125I brachytherapy for localized prostate cancer: a single institution experience.

    PubMed

    Guarneri, Alessia; Botticella, Angela; Filippi, Andrea Riccardo; Munoz, Fernando; Beltramo, Giancarlo; Casetta, Giovanni; Giglioli, Francesca Romana; Tizzani, Alessandro; Ragona, Riccardo; Ricardi, Umberto

    2013-01-01

    To evaluate the clinical outcome of a cohort of localized prostate cancer patients treated with 125I permanent brachytherapy at the University of Turin. A retrospective analysis was carried out on 167 consecutive patients with early stage prostate adenocarcinoma who underwent 125I brachytherapy between January 2003 and December 2010. A minimum follow-up of ≥ 12 months was mandatory for inclusion. Biochemical disease-free survival (defined on the basis of the ASTRO definition and the ASTRO-Phoenix definition) was chosen as the primary end point. Secondary end points were gastrointestinal and genitourinary toxicity (acute and late, defined according to the RTOG scale). With a median follow-up of 42 months (range, 13.5-90.7), biochemical disease-free survival at 3 and 5 years was respectively 91.1% and 85.7%, according to the ASTRO definition and 94.5% and 85.1% according to ASTRO-Phoenix definition (for statistical purposes, only the ASTRO definition was used). Hormone treatment and nadir PSA (cutoff of 0.35 ng/ml) were the only factors affecting biochemical disease-free survival both on univariate (P = 0.02 and P = 0.001, respectively) and multivariate analysis (HR 0.024; P = 0.021 and HR 21.6; P = 0.006, respectively). Only 3.6% of patients experienced ≥ grade 3 acute urinary toxicity and 5% ≥ grade 3 late urinary toxicity. Prior transurethral prostate resection was the only independent predictor of grade 3 late urinary toxicity on multivariate analysis (HR 0.13; P = 0.009). This mono-institutional series confirmed that brachytherapy is an effective and safe treatment modality for localized prostate cancer, with acceptable short- and long-term morbidity rates.

  13. Radiation Exposure and Safety Precautions Following 131Cs Brachytherapy in Patients with Brain Tumors.

    PubMed

    Yondorf, Menachem Z; Schwartz, Theodore H; Boockvar, John A; Pannullo, Susan; Stieg, Philip; Sabbas, Albert; Pavese, Albert; Trichter, Samuel; Nedialkova, Lucy; Parashar, Bhupesh; Nori, Dattatreyudu; Chao, K S Clifford; Wernicke, A Gabriella

    2017-04-01

    Cesium-131 (Cs) brachytherapy is a safe and convenient treatment option for patients with resected brain tumors. This study prospectively analyzes radiation exposure in the patient population who were treated with a maximally safe neurosurgical resection and Cs brachytherapy. Following implantation, radiation dose rate measurements were taken at the surface, 35 cm, and 100 cm distances. Using the half-life of Cs (9.69 d), the dose rates were extrapolated at these distances over a period of time (t = 30 d). Data from dosimetry badges and rings worn by surgeons and radiation oncologists were collected and analyzed. Postoperatively, median dose rate was 0.2475 mSv h, 0.01 mSv h, and 0.001 mSv h and at 30 d post-implant, 0.0298 mSv h, 0.0012 mSv h, and 0.0001 mSv h at the surface, 35 cm, and 100 cm, respectively. All but one badge and ring measured a dose equivalent corresponding to ~0 mSv h, while 1 badge measured 0.02/0.02/0.02 mSv h. There was a significant correlation between the number of seeds implanted and dose rate at the surface (p = 0.0169). When stratified by the number of seeds: 4-15 seeds (n = 14) and 20-50 seeds (n = 4) had median dose rates of 0.1475 mSv h and 0.5565 mSv h, respectively (p = 0.0015). Using National Council on Radiation Protection guidelines, this study shows that dose equivalent from permanent Cs brachytherapy for the treatment of brain tumors is limited, and it maintains safe levels of exposure to family and medical personnel. Such information is critical knowledge for the neurosurgeons, radiation oncologists, nurses, hospital staff, and family as this method is gaining nationwide popularity.

  14. [How to prepare the brachytherapy of the future].

    PubMed

    Hannoun-Lévi, J-M; Peiffert, D

    2013-10-01

    For more than a century, brachytherapy has been a treatment of choice for delivering a high dose in a small volume. However, over the past 15 years, this irradiation technique has stalled. Even so, brachytherapy allows the delivery of the right dose at the right place by dispensing with target volume motion and repositioning. The evolution of brachytherapy can be based on a road-map including at least the following three points: the acquisition of clinical evidence, teaching and valuation of the procedures. The evolution of brachytherapy will be also impacted by technological considerations (end of the production of low dose rate 192 iridium wires). Regarding the evolution toward a personalized treatment, brachytherapy of the future should take its place as a partner of other modern external beam radiation techniques, be performed by experimented actors (physicians, physicists, technicians, etc.) who received adequate training, and be valued in proportion to the delivered medical service.

  15. Improving the efficiency of image guided brachytherapy in cervical cancer

    PubMed Central

    Franklin, Adrian; Ajaz, Mazhar; Stewart, Alexandra

    2016-01-01

    Brachytherapy is an essential component of the treatment of locally advanced cervical cancers. It enables the dose to the tumor to be boosted whilst allowing relative sparing of the normal tissues. Traditionally, cervical brachytherapy was prescribed to point A but since the GEC-ESTRO guidelines were published in 2005, there has been a move towards prescribing the dose to a 3D volume. Image guided brachytherapy has been shown to reduce local recurrence, and improve survival and is optimally predicated on magnetic resonance imaging. Radiological studies, patient workflow, operative parameters, and intensive therapy planning can represent a challenge to clinical resources. This article explores the ways, in which 3D conformal brachytherapy can be implemented and draws findings from recent literature and a well-developed hospital practice in order to suggest ways to improve the efficiency and efficacy of a brachytherapy service. Finally, we discuss relatively underexploited translational research opportunities. PMID:28115963

  16. Penile brachytherapy: Results for 49 patients

    SciTech Connect

    Crook, Juanita M. . E-mail: juanita.crook@rmp.uhn.on.ca; Jezioranski, John; Grimard, Laval; Esche, Bernd; Pond, G.

    2005-06-01

    Purpose: To report results for 49 men with squamous cell carcinoma (SCC) of the penis treated with primary penile interstitial brachytherapy at one of two institutions: the Ottawa Regional Cancer Center, Ottawa, and the Princess Margaret Hospital, Toronto, Ontario, Canada. Methods and Materials: From September 1989 to September 2003, 49 men (mean age, 58 years; range, 22-93 years) had brachytherapy for penile SCC. Fifty-one percent of tumors were T1, 33% T2, and 8% T3; 4% were in situ and 4% Tx. Grade was well differentiated in 31%, moderate in 45%, and poor in 2%; grade was unspecified for 20%. One tumor was verrucous. All tumors in Toronto had pulsed dose rate (PDR) brachytherapy (n = 23), whereas those in Ottawa had either Iridium wire (n 22) or seeds (n = 4). Four patients had a single plane implant with a plastic tube technique, and all others had a volume implant with predrilled acrylic templates and two or three parallel planes of needles (median, six needles). Mean needle spacing was 13.5 mm (range, 10-18 mm), mean dose rate was 65 cGy/h (range, 33-160 cGy/h), and mean duration was 98.8 h (range, 36-188 h). Dose rates for PDR brachytherapy were 50-61.2 cGy/h, with no correction in total dose, which was 60 Gy in all cases. Results: Median follow-up was 33.4 months (range, 4-140 months). At 5 years, actuarial overall survival was 78.3% and cause-specific survival 90.0%. Four men died of penile cancer, and 6 died of other causes with no evidence of recurrence. The cumulative incidence rate for never having experienced any type of failure at 5 years was 64.4% and for local failure was 85.3%. All 5 patients with local failure were successfully salvaged by surgery; 2 other men required penectomy for necrosis. The soft tissue necrosis rate was 16% and the urethral stenosis rate 12%. Of 8 men with regional failure, 5 were salvaged by lymph node dissection with or without external radiation. All 4 men with distant failure died of disease. Of 49 men, 42 had an intact

  17. [INSEE's permanent demographic sample].

    PubMed

    Sautory, O

    1987-01-01

    This article discusses the permanent demographic sample survey developed by France's Institut National de la Statistique et des Etudes Economiques (INSEE), which has been in use in that country since the census of 1968. Approximately one percent of the metropolitan population of France was chosen for inclusion by birthdate. By adding data on marriage, births of children, change of residence, schooling, employment status, and death to each person's file, longitudinal studies of fertility, nuptiality, and mortality can be conducted. Two such studies are included as examples of how the permanent sample survey can be best put to use.

  18. Local tumor control after {sup 106}Ru brachytherapy of choroidal melanoma

    SciTech Connect

    Damato, Bertil . E-mail: Bertil@damato.co.uk; Patel, Imran; Campbell, Ian R.; Mayles, Helen M.; Errington, R. Douglas

    2005-10-01

    Purpose To report on local tumor control after {sup 106}Ru brachytherapy for choroidal melanoma. Methods and Materials A total of 458 patients with choroidal melanoma were treated at a single institution between January 1993 and December 2001. The tumors had a median longest basal dimension of 10.6 mm and a median height of 3.2 mm. The brachytherapy was administered using a 15- or 20-mm plaque. For posterior tumors, the plaque was positioned eccentrically with its posterior edge aligned with the posterior tumor margin to reduce the radiation dose to the optic disk and fovea. A minimal scleral dose sufficient to cause visible choroidal atrophy provided a permanent ophthalmoscopic record of the distribution of choroidal irradiation. If radiotherapy to the posterior tumor was uncertain, adjunctive transpupillary thermotherapy was administered 6 months postoperatively. Results The actuarial rates of tumor recurrence were 1%, 2%, and 3% at 2, 5, and 7 years, respectively. Local tumor recurrence correlated with the longest basal tumor dimension (Cox univariate analysis, p = 0.02, risk ratio 1.41, 95% confidence interval 1.06-1.88). Seven of the nine eyes with recurrent tumor were salvaged with additional conservative therapy. Conclusion The low rate of local tumor recurrence suggests that ruthenium plaque radiotherapy is effective with good case selection and if special measures are taken to ensure that the plaque is positioned correctly.

  19. Dose heterogeneity correction for low-energy brachytherapy sources using dual-energy CT images

    NASA Astrophysics Data System (ADS)

    Mashouf, S.; Lechtman, E.; Lai, P.; Keller, B. M.; Karotki, A.; Beachey, D. J.; Pignol, J. P.

    2014-09-01

    Permanent seed implant brachytherapy is currently used for adjuvant radiotherapy of early stage prostate and breast cancer patients. The current standard for calculation of dose around brachytherapy sources is based on the AAPM TG-43 formalism, which generates the dose in a homogeneous water medium. Recently, AAPM TG-186 emphasized the importance of accounting for tissue heterogeneities. We have previously reported on a methodology where the absorbed dose in tissue can be obtained by multiplying the dose, calculated by the TG-43 formalism, by an inhomogeneity correction factor (ICF). In this work we make use of dual energy CT (DECT) images to extract ICF parameters. The advantage of DECT over conventional CT is that it eliminates the need for tissue segmentation as well as assignment of population based atomic compositions. DECT images of a heterogeneous phantom were acquired and the dose was calculated using both TG-43 and TG-43 × \\text{ICF} formalisms. The results were compared to experimental measurements using Gafchromic films in the mid-plane of the phantom. For a seed implant configuration of 8 seeds spaced 1.5 cm apart in a cubic structure, the gamma passing score for 2%/2 mm criteria improved from 40.8% to 90.5% when ICF was applied to TG-43 dose distributions.

  20. Dose heterogeneity correction for low-energy brachytherapy sources using dual-energy CT images.

    PubMed

    Mashouf, S; Lechtman, E; Lai, P; Keller, B M; Karotki, A; Beachey, D J; Pignol, J P

    2014-09-21

    Permanent seed implant brachytherapy is currently used for adjuvant radiotherapy of early stage prostate and breast cancer patients. The current standard for calculation of dose around brachytherapy sources is based on the AAPM TG-43 formalism, which generates the dose in a homogeneous water medium. Recently, AAPM TG-186 emphasized the importance of accounting for tissue heterogeneities. We have previously reported on a methodology where the absorbed dose in tissue can be obtained by multiplying the dose, calculated by the TG-43 formalism, by an inhomogeneity correction factor (ICF). In this work we make use of dual energy CT (DECT) images to extract ICF parameters. The advantage of DECT over conventional CT is that it eliminates the need for tissue segmentation as well as assignment of population based atomic compositions. DECT images of a heterogeneous phantom were acquired and the dose was calculated using both TG-43 and TG-43 [Formula: see text] formalisms. The results were compared to experimental measurements using Gafchromic films in the mid-plane of the phantom. For a seed implant configuration of 8 seeds spaced 1.5 cm apart in a cubic structure, the gamma passing score for 2%/2 mm criteria improved from 40.8% to 90.5% when ICF was applied to TG-43 dose distributions.

  1. Alkaline "Permanent" Paper.

    ERIC Educational Resources Information Center

    Pacey, Antony

    1991-01-01

    Discussion of paper manufacturing processes and their effects on library materials focuses on the promotion of alkaline "permanent" paper, with less acid, by Canadian library preservation specialists. Standards for paper acidity are explained; advantages of alkaline paper are described, including decreased manufacturing costs; and…

  2. Technical note: cone beam CT imaging for 3D image guided brachytherapy for gynecological HDR brachytherapy.

    PubMed

    Reniers, Brigitte; Verhaegen, Frank

    2011-05-01

    This paper focuses on a novel image guidance technique for gynecological brachytherapy treatment. The present standard technique is orthogonal x-ray imaging to reconstruct the 3D position of the applicator when the availability of CT or MR is limited. Our purpose is to introduce 3D planning in the brachytherapy suite using a cone beam CT (CBCT) scanner dedicated to brachytherapy. This would avoid moving the patient between imaging and treatment procedures which may cause applicator motion. This could be used to replace the x-ray images or to verify the treatment position immediately prior to dose delivery. The sources of CBCT imaging artifacts in the case of brachytherapy were identified and removed where possible. The image quality was further improved by modifying the x-ray tube voltage, modifying the compensator bowtie filter and optimizing technical parameters such as the detector gain or tube current. The image quality was adequate to reconstruct the applicators in the treatment planning system. The position of points A and the localization of the organs at risk (OAR) ICRU points is easily achieved. This allows identification of cases where the rectum had moved with respect to the ICRU point which would require asymmetrical source loading. A better visualization is a first step toward a better sparing of the OAR. Treatment planning for gynecological brachytherapy is aided by CBCT images. CBCT presents advantages over CT: acquisition in the treatment room and in the treatment position due to the larger clearance of the CBCT, thereby reducing problems associated to moving patients between rooms.

  3. Three-Dimensional Imaging in Gynecologic Brachytherapy: A Survey of the American Brachytherapy Society

    SciTech Connect

    Viswanathan, Akila N.; Erickson, Beth A.

    2010-01-15

    Purpose: To determine current practice patterns with regard to three-dimensional (3D) imaging for gynecologic brachytherapy among American Brachytherapy Society (ABS) members. Methods and Materials: Registered physician members of the ABS received a 19-item survey by e-mail in August 2007. This report excludes physicians not performing brachytherapy for cervical cancer. Results: Of the 256 surveys sent, we report results for 133 respondents who perform one or more implantations per year for locally advanced cervical cancer. Ultrasound aids 56% of physicians with applicator insertion. After insertion, 70% of physicians routinely obtain a computed tomography (CT) scan. The majority (55%) use CT rather than X-ray films (43%) or magnetic resonance imaging (MRI; 2%) for dose specification to the cervix. However, 76% prescribe to Point A alone instead of using a 3D-derived tumor volume (14%), both Point A and tumor volume (7%), or mg/h (3%). Those using 3D imaging routinely contour the bladder and rectum (94%), sigmoid (45%), small bowel (38%), and/or urethra (8%) and calculate normal tissue dose-volume histogram (DVH) analysis parameters including the D2cc (49%), D1cc (36%), D0.1cc (19%), and/or D5cc (19%). Respondents most commonly modify the treatment plan based on International Commission on Radiation Units bladder and/or rectal point dose values (53%) compared with DVH values (45%) or both (2%). Conclusions: More ABS physician members use CT postimplantation imaging than plain films for visualizing the gynecologic brachytherapy apparatus. However, the majority prescribe to Point A rather than using 3D image based dosimetry. Use of 3D image-based treatment planning for gynecologic brachytherapy has the potential for significant growth in the United States.

  4. The second decade of prostate brachytherapy: evidence and cost based outcomes.

    PubMed

    Vigneri, Philip; Herati, Amin S; Potters, Louis

    2010-01-01

    Permanent prostate brachytherapy (PPB) is an established and successful treatment option for localized prostate cancer. Under ultrasound guidance, the procedure can be performed in the ambulatory setting and represents a conformal, ablative technique. For low-risk patients, PSA control is expected in over 90% with outcomes now reported past 12 years. High-risk patients can benefit from PPB as part of a program that may include external beam therapy and androgen ablation. Morbidity tends to center on urinary function, but with modern adaptive techniques, this can be minimized. Sexual functioning is likely disturbed less with PPB than with surgery or external beam radiation therapy. Finally, cost benefit analysis confirms PPB as the most attractive radiation option. With the incidence of prostate cancer still rising, PPB remains a key treatment option in the successful management of prostate cancers. Copyright 2010 Elsevier Inc. All rights reserved.

  5. Computer-assisted CT-guided stereotactic biopsy and brachytherapy of brain tumors.

    PubMed

    Quiñones-Molina, R; Alaminos, A; Molina, H; Muñoz, J; López, G; Alvarez, L; Ortega, I; Piedra, J; Soler, W; Torres, A

    1994-01-01

    From March 1991 to September 1993, 26 patients (aged 4-78 years) with brain tumors (4 glioblastoma multiforme, 10 nonglioblastoma multiforme, 1 mixed oligoastrocytoma, 2 carniopharyngiomas, 2 meningiomas and 7 metastases) were treated with stereotactic techniques at the Centro Internacional de Restauración Neurológica, La Habana, Cuba. A total of 28 stereotactic surgical procedures were performed with no operative mortality; they included biopsies in all cases, 1 stereotactic microsurgical resection and 12 permanent implants of 192Ir, followed by external beam fractionated radiation therapy (40-60 Gy). The present paper shows that the combined use of a stereotactic approach, a comprehensive and reliable stereotactic dosimetric planning system, stereotactic brachytherapy with 192Ir and complementary percutaneous radiation treatment constitutes a promising strategy for brain tumor management.

  6. Recent developments and best practice in brachytherapy treatment planning

    PubMed Central

    2014-01-01

    Brachytherapy has evolved over many decades, but more recently, there have been significant changes in the way that brachytherapy is used for different treatment sites. This has been due to the development of new, technologically advanced computer planning systems and treatment delivery techniques. Modern, three-dimensional (3D) imaging modalities have been incorporated into treatment planning methods, allowing full 3D dose distributions to be computed. Treatment techniques involving online planning have emerged, allowing dose distributions to be calculated and updated in real time based on the actual clinical situation. In the case of early stage breast cancer treatment, for example, electronic brachytherapy treatment techniques are being used in which the radiation dose is delivered during the same procedure as the surgery. There have also been significant advances in treatment applicator design, which allow the use of modern 3D imaging techniques for planning, and manufacturers have begun to implement new dose calculation algorithms that will correct for applicator shielding and tissue inhomogeneities. This article aims to review the recent developments and best practice in brachytherapy techniques and treatments. It will look at how imaging developments have been incorporated into current brachytherapy treatment and how these developments have played an integral role in the modern brachytherapy era. The planning requirements for different treatments sites are reviewed as well as the future developments of brachytherapy in radiobiology and treatment planning dose calculation. PMID:24734939

  7. Multihelix rotating shield brachytherapy for cervical cancer

    PubMed Central

    Dadkhah, Hossein; Kim, Yusung; Wu, Xiaodong; Flynn, Ryan T.

    2015-01-01

    Purpose: To present a novel brachytherapy technique, called multihelix rotating shield brachytherapy (H-RSBT), for the precise angular and linear positioning of a partial shield in a curved applicator. H-RSBT mechanically enables the dose delivery using only linear translational motion of the radiation source/shield combination. The previously proposed approach of serial rotating shield brachytherapy (S-RSBT), in which the partial shield is rotated to several angular positions at each source dwell position [W. Yang et al., “Rotating-shield brachytherapy for cervical cancer,” Phys. Med. Biol. 58, 3931–3941 (2013)], is mechanically challenging to implement in a curved applicator, and H-RSBT is proposed as a feasible solution. Methods: A Henschke-type applicator, designed for an electronic brachytherapy source (Xoft Axxent™) and a 0.5 mm thick tungsten partial shield with 180° or 45° azimuthal emission angles and 116° asymmetric zenith angle, is proposed. The interior wall of the applicator contains six evenly spaced helical keyways that rigidly define the emission direction of the partial radiation shield as a function of depth in the applicator. The shield contains three uniformly distributed protruding keys on its exterior wall and is attached to the source such that it rotates freely, thus longitudinal translational motion of the source is transferred to rotational motion of the shield. S-RSBT and H-RSBT treatment plans with 180° and 45° azimuthal emission angles were generated for five cervical cancer patients with a diverse range of high-risk target volume (HR-CTV) shapes and applicator positions. For each patient, the total number of emission angles was held nearly constant for S-RSBT and H-RSBT by using dwell positions separated by 5 and 1.7 mm, respectively, and emission directions separated by 22.5° and 60°, respectively. Treatment delivery time and tumor coverage (D90 of HR-CTV) were the two metrics used as the basis for evaluation and

  8. Multihelix rotating shield brachytherapy for cervical cancer

    SciTech Connect

    Dadkhah, Hossein; Kim, Yusung; Flynn, Ryan T.; Wu, Xiaodong

    2015-11-15

    Purpose: To present a novel brachytherapy technique, called multihelix rotating shield brachytherapy (H-RSBT), for the precise angular and linear positioning of a partial shield in a curved applicator. H-RSBT mechanically enables the dose delivery using only linear translational motion of the radiation source/shield combination. The previously proposed approach of serial rotating shield brachytherapy (S-RSBT), in which the partial shield is rotated to several angular positions at each source dwell position [W. Yang et al., “Rotating-shield brachytherapy for cervical cancer,” Phys. Med. Biol. 58, 3931–3941 (2013)], is mechanically challenging to implement in a curved applicator, and H-RSBT is proposed as a feasible solution. Methods: A Henschke-type applicator, designed for an electronic brachytherapy source (Xoft Axxent™) and a 0.5 mm thick tungsten partial shield with 180° or 45° azimuthal emission angles and 116° asymmetric zenith angle, is proposed. The interior wall of the applicator contains six evenly spaced helical keyways that rigidly define the emission direction of the partial radiation shield as a function of depth in the applicator. The shield contains three uniformly distributed protruding keys on its exterior wall and is attached to the source such that it rotates freely, thus longitudinal translational motion of the source is transferred to rotational motion of the shield. S-RSBT and H-RSBT treatment plans with 180° and 45° azimuthal emission angles were generated for five cervical cancer patients with a diverse range of high-risk target volume (HR-CTV) shapes and applicator positions. For each patient, the total number of emission angles was held nearly constant for S-RSBT and H-RSBT by using dwell positions separated by 5 and 1.7 mm, respectively, and emission directions separated by 22.5° and 60°, respectively. Treatment delivery time and tumor coverage (D{sub 90} of HR-CTV) were the two metrics used as the basis for evaluation and

  9. [Perioperative interstitial brachytherapy for recurrent keloid scars].

    PubMed

    Rio, E; Bardet, E; Peuvrel, P; Martinet, L; Perrot, P; Baraer, F; Loirat, Y; Sartre, J-Y; Malard, O; Ferron, C; Dreno, B

    2010-01-01

    Evaluation of the results of perioperative interstitial brachytherapy with low dose-rate (LDR) Ir-192 in the treatment of keloid scars. We performed a retrospective analysis of 73 histologically confirmed keloids (from 58 patients) resistant to medicosurgical treated by surgical excision plus early perioperative brachytherapy. All lesions were initially symptomatic. Local control was evaluated by clinical evaluation. Functional and cosmetic results were assessed in terms of patient responses to a self-administered questionnaire. Median age was 28 years (range 13-71 years). Scars were located as follows: 37% on the face, 32% on the trunk or abdomen, 16% on the neck, and 15% on the arms or legs. The mean delay before loading was four hours (range, 1-6h). The median dose was 20Gy (range, 15-40Gy). Sixty-four scars (from 53 patients) were evaluated. Local control was 86% (follow-up, 44.5 months; range, 14-150 months). All relapses occurred early - within 2 years posttreatment. At 20 months, survival without recurrence was significantly lower when treated lengths were more than 6cm long. The rate was 100% for treated scars below 4.5cm in length, 95% (95% CI: 55-96) for those 4.5-6cm long, and 75% (95% CI: 56-88) beyond 6cm (p=0.038). Of the 35 scars (28 patients) whose results were reassessed, six remained symptomatic and the esthetic results were considered to be good in 51% (18/35) and average in 37% (13/35) (median follow-up, 70 months; range, 16-181 months). Early perioperative LDR brachytherapy delivering 20Gy at 5mm reduced the rate of recurrent keloids resistant to other treatments and gave good functional results. 2009 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  10. A Novel MRI Marker for Prostate Brachytherapy

    SciTech Connect

    Frank, Steven J. Stafford, R. Jason; Bankson, James A.; Li Chun; Swanson, David A.; Kudchadker, Rajat J.; Martirosyan, Karen S.

    2008-05-01

    Purpose: Magnetic resonance imaging (MRI) is the optimal imaging modality for the prostate and surrounding critical organ structures. However, on MRI, the titanium radioactive seeds used for brachytherapy appear as black holes (negative contrast) and cannot be accurately localized. We sought to develop an encapsulated contrast agent marker (ECAM) with high-signal intensity on MRI to permit accurate localization of radioactive seeds with MRI during and after prostate brachytherapy. Methods and Materials: We investigated several agents with paramagnetic and superparamagnetic properties. The agents were injected into titanium, acrylic, and glass seeds, which were linked together in various combinations and imaged with MRI. The agent with the greatest T1-weighted signal was tested further in a canine prostate and agarose phantom. Studies were performed on a 1.5-T clinical MRI scanner. Results: The cobalt-chloride complex contrast (C4) agent with stoichiometry (CoCl{sub 2}){sub 0.8}(C{sub 2}H{sub 5}NO{sub 2}){sub 0.2} had the greatest T1-weighted signal (positive contrast) with a relaxivity ratio >1 (r{sub 2}/r{sub 1} = 1.21 {+-} 0.29). Acrylic-titanium and glass-titanium seed strands were clearly visualized with the encapsulated contrast agent marker. Conclusion: We have developed a novel ECAM that permits positive identification of the radioactive seeds used for prostate brachytherapy on MRI. Preclinical in vitro phantom studies and in vivo canine studies are needed to further optimize MRI sequencing techniques to facilitate MRI-based dosimetry.

  11. Needle deflection estimation: prostate brachytherapy phantom experiments.

    PubMed

    Sadjadi, Hossein; Hashtrudi-Zaad, Keyvan; Fichtinger, Gabor

    2014-11-01

    The performance of a fusion-based needle deflection estimation method was experimentally evaluated using prostate brachytherapy phantoms. The accuracy of the needle deflection estimation was determined. The robustness of the approach with variations in needle insertion speed and soft tissue biomechanical properties was investigated. A needle deflection estimation method was developed to determine the amount of needle bending during insertion into deformable tissue by combining a kinematic deflection model with measurements taken from two electromagnetic trackers placed at the tip and the base of the needle. Experimental verification of this method for use in prostate brachytherapy needle insertion procedures was performed. A total of 21 beveled tip, 18 ga, 200 mm needles were manually inserted at various speeds through a template and toward different targets distributed within 3 soft tissue mimicking polyvinyl chloride prostate phantoms of varying stiffness. The tracked positions of both the needle tip and base were recorded, and Kalman filters were applied to fuse the sensory information. The estimation results were validated using ground truth obtained from fluoroscopy images. The manual insertion speed ranged from 8 to 34 mm/s, needle deflection ranged from 5 to 8 mm at an insertion depth of 76 mm, and the elastic modulus of the soft tissue ranged from 50 to 150 kPa. The accuracy and robustness of the estimation method were verified within these ranges. When compared to purely model-based estimation, we observed a reduction in needle tip position estimation error by [Formula: see text] % (mean [Formula: see text] SD) and the cumulative deflection error by [Formula: see text] %. Fusion of electromagnetic sensors demonstrated significant improvement in estimating needle deflection compared to model-based methods. The method has potential clinical applicability in the guidance of needle placement medical interventions, particularly prostate brachytherapy.

  12. Selective identification of different brachytherapy sources, ferromagnetic seeds, and fiducials in the prostate using an automated seed sorting algorithm.

    PubMed

    Davis, Brian J; Brinkmann, Debra H; Kruse, Jon J; Herman, Michael G; LaJoie, Wayne N; Schwartz, David J; Pisansky, Thomas M; Kline, Robert W

    2004-01-01

    Routine permanent prostate brachytherapy (PPB) includes CT-based postimplant dosimetry (PID). A method of identifying different source types from CT data in the same implant volume is described. A previously described automatic method for seed localization using CT data is used in this study. Two cases were analyzed: a PPB case with (103)Pd followed by salvage (125)I implantation, both performed at another institution, and a cadaver case where 4 different seed types, including ferromagnetic seeds, and fiducials were implanted. Automatic segregation of different seed types with minimal manual correction is demonstrated using the described localization algorithm. The process is confirmed accurate by comparison of plain film radiographs to CT data and digitally reconstructed radiographs. Unique identification of different source types, including PPB seeds, fiducial markers, and ferromagnetic seeds in permanent implants is possible and permits dosimetric analyses that are spatially coincident.

  13. [Pulsed-dose rate brachytherapy in cervical cancers: why, how?].

    PubMed

    Mazeron, R; Dumas, I; Martin, V; Martinetti, F; Benhabib-Boukhelif, W; Gensse, M-C; Chargari, C; Guemnie-Tafo, A; Haie-Méder, C

    2014-10-01

    The end of the production of 192 iridium wires terminates low dose rate brachytherapy and requires to move towards pulsed-dose rate or high-dose rate brachytherapy. In the case of gynecological cancers, technical alternatives exist, and many teams have already taken the step of pulsed-dose rate for scientific reasons. Using a projector source is indeed a prerequisite for 3D brachytherapy, which gradually installs as a standard treatment in the treatment of cervical cancers. For other centers, this change implies beyond investments in equipment and training, organizational consequences to ensure quality.

  14. Brachytherapy in the treatment of cervical cancer: a review

    PubMed Central

    Banerjee, Robyn; Kamrava, Mitchell

    2014-01-01

    Dramatic advances have been made in brachytherapy for cervical cancer. Radiation treatment planning has evolved from two-dimensional to three-dimensional, incorporating magnetic resonance imaging and/or computed tomography into the treatment paradigm. This allows for better delineation and coverage of the tumor, as well as improved avoidance of surrounding organs. Consequently, advanced brachytherapy can achieve very high rates of local control with a reduction in morbidity, compared with historic approaches. This review provides an overview of state-of-the-art gynecologic brachytherapy, with a focus on recent advances and their implications for women with cervical cancer. PMID:24920937

  15. Variable Permanent Magnet Quadrupole

    SciTech Connect

    Mihara, T.; Iwashita, Y.; Kumada, M.; Spencer, C.M.; /SLAC

    2007-05-23

    A permanent magnet quadrupole (PMQ) is one of the candidates for the final focus lens in a linear collider. An over 120 T/m strong variable permanent magnet quadrupole is achieved by the introduction of saturated iron and a 'double ring structure'. A fabricated PMQ achieved 24 T integrated gradient with 20 mm bore diameter, 100 mm magnet diameter and 20 cm pole length. The strength of the PMQ is adjustable in 1.4 T steps, due to its 'double ring structure': the PMQ is split into two nested rings; the outer ring is sliced along the beam line into four parts and is rotated to change the strength. This paper describes the variable PMQ from fabrication to recent adjustments.

  16. Managing Permanent Objects

    DTIC Science & Technology

    1984-11-01

    sorage me hanism is the Chunk Management System ( CMS ). CMS provides a database-like interface for POMW. On first reference to a permanent object POMS...19] M.P. Atkinson, K.J. Chisholm, and W.P. Cockshott. CMS - A Chunk Management System . Technical Report CSR-110-82, Department of Computer Science...database manager . Creating and using emibedded systems is not always bad. In most large programming projets one ends up constructing and using some sort

  17. Permanent magnet design methodology

    NASA Technical Reports Server (NTRS)

    Leupold, Herbert A.

    1991-01-01

    Design techniques developed for the exploitation of high energy magnetically rigid materials such as Sm-Co and Nd-Fe-B have resulted in a revolution in kind rather than in degree in the design of a variety of electron guidance structures for ballistic and aerospace applications. Salient examples are listed. Several prototype models were developed. These structures are discussed in some detail: permanent magnet solenoids, transverse field sources, periodic structures, and very high field structures.

  18. Postoperative permanent pressure alopecia.

    PubMed

    Chang, Zi Yun; Ngian, Jan; Chong, Claudia; Chong, Chin Ted; Liew, Qui Yin

    2016-04-01

    A 49-year-old Chinese female underwent elective laparoscopic assisted Whipple's surgery lasting 12 h. This was complicated by postoperative pressure alopecia at the occipital area of the scalp. Pressure-induced hair loss after general anaesthesia is uncommon and typically temporary, but may be disconcerting to the patient. We report this case of postoperative permanent pressure alopecia due to its rarity in the anaesthesia/local literature, and review the risk factors for its development.

  19. Image-guided high-dose-rate brachytherapy in inoperable endometrial cancer

    PubMed Central

    Petsuksiri, J; Chansilpa, Y; Hoskin, P J

    2014-01-01

    Inoperable endometrial cancer may be treated with curative aim using radical radiotherapy alone. The radiation techniques are external beam radiotherapy (EBRT) alone, EBRT plus brachytherapy and brachytherapy alone. Recently, high-dose-rate brachytherapy has been used instead of low-dose-rate brachytherapy. Image-guided brachytherapy enables sufficient coverage of tumour and reduction of dose to the organs at risk, thus increasing the therapeutic ratio of treatment. Local control rates with three-dimensional brachytherapy appear better than with conventional techniques (about 90–100% and 70–90%, respectively). PMID:24807067

  20. American Brachytherapy Society Task Group Report: Long-term control and toxicity with brachytherapy for localized breast cancer.

    PubMed

    Shaitelman, Simona F; Amendola, Beatriz; Khan, Atif; Beriwal, Sushil; Rabinovitch, Rachel; Demanes, D Jeffrey; Kim, Leonard H; Cuttino, Laurie

    There has been significant controversy regarding the equivalency of accelerated partial breast irradiation to whole-breast irradiation. With the recent publication of a large, randomized trial comparing these two treatment modalities, an update on the current state of knowledge of brachytherapy-based accelerated partial breast irradiation, with respect to local control and toxicities, would be useful to practitioners and patients. A systematic literature review was conducted examining articles published between January 2000 and April 2016 on the topics "brachytherapy" and "breast." A total of 67 articles met inclusion criteria, providing outcomes on local tumor control and/or toxicity for breast brachytherapy. Reported 5-year local failure rates were 1.4-6.1% for multicatheter interstitial brachytherapy (MIB) and 0-5.7% for single-entry brachytherapy catheters when delivered to patients with standard selection criteria. Toxicity profiles are acceptable, with cosmetic outcomes comparable to whole-breast irradiation. The reported rates of infection were 0-12%. Symptomatic fat necrosis was found in 0-12% and 0-3.2% of patients treated with MIB and single-entry brachytherapy catheters, respectively. Late Grade ≥3 telangiectasias and fibrosis were reported in 0-8% and 0-9.1% of patients treated with MIB, respectively. These side effects were less common with single-entry brachytherapy catheters (0-2.0% and 0%, respectively). Breast brachytherapy is a treatment technique that provides acceptable rates of local control in select patients, as demonstrated by Level I evidence. The side effect profile of this treatment is well documented and should be shared with patients when considering this treatment modality. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  1. Dosimetric characterization and output verification for conical brachytherapy surface applicators. Part I. Electronic brachytherapy source

    PubMed Central

    Fulkerson, Regina K.; Micka, John A.; DeWerd, Larry A.

    2014-01-01

    Purpose: Historically, treatment of malignant surface lesions has been achieved with linear accelerator based electron beams or superficial x-ray beams. Recent developments in the field of brachytherapy now allow for the treatment of surface lesions with specialized conical applicators placed directly on the lesion. Applicators are available for use with high dose rate (HDR) 192Ir sources, as well as electronic brachytherapy sources. Part I of this paper will discuss the applicators used with electronic brachytherapy sources; Part II will discuss those used with HDR 192Ir sources. Although the use of these applicators has gained in popularity, the dosimetric characteristics including depth dose and surface dose distributions have not been independently verified. Additionally, there is no recognized method of output verification for quality assurance procedures with applicators like these. Existing dosimetry protocols available from the AAPM bookend the cross-over characteristics of a traditional brachytherapy source (as described by Task Group 43) being implemented as a low-energy superficial x-ray beam (as described by Task Group 61) as observed with the surface applicators of interest. Methods: This work aims to create a cohesive method of output verification that can be used to determine the dose at the treatment surface as part of a quality assurance/commissioning process for surface applicators used with HDR electronic brachytherapy sources (Part I) and 192Ir sources (Part II). Air-kerma rate measurements for the electronic brachytherapy sources were completed with an Attix Free-Air Chamber, as well as several models of small-volume ionization chambers to obtain an air-kerma rate at the treatment surface for each applicator. Correction factors were calculated using MCNP5 and EGSnrc Monte Carlo codes in order to determine an applicator-specific absorbed dose to water at the treatment surface from the measured air-kerma rate. Additionally, relative dose

  2. Dosimetric characterization and output verification for conical brachytherapy surface applicators. Part I. Electronic brachytherapy source

    SciTech Connect

    Fulkerson, Regina K. Micka, John A.; DeWerd, Larry A.

    2014-02-15

    Purpose: Historically, treatment of malignant surface lesions has been achieved with linear accelerator based electron beams or superficial x-ray beams. Recent developments in the field of brachytherapy now allow for the treatment of surface lesions with specialized conical applicators placed directly on the lesion. Applicators are available for use with high dose rate (HDR){sup 192}Ir sources, as well as electronic brachytherapy sources. Part I of this paper will discuss the applicators used with electronic brachytherapy sources; Part II will discuss those used with HDR {sup 192}Ir sources. Although the use of these applicators has gained in popularity, the dosimetric characteristics including depth dose and surface dose distributions have not been independently verified. Additionally, there is no recognized method of output verification for quality assurance procedures with applicators like these. Existing dosimetry protocols available from the AAPM bookend the cross-over characteristics of a traditional brachytherapy source (as described by Task Group 43) being implemented as a low-energy superficial x-ray beam (as described by Task Group 61) as observed with the surface applicators of interest. Methods: This work aims to create a cohesive method of output verification that can be used to determine the dose at the treatment surface as part of a quality assurance/commissioning process for surface applicators used with HDR electronic brachytherapy sources (Part I) and{sup 192}Ir sources (Part II). Air-kerma rate measurements for the electronic brachytherapy sources were completed with an Attix Free-Air Chamber, as well as several models of small-volume ionization chambers to obtain an air-kerma rate at the treatment surface for each applicator. Correction factors were calculated using MCNP5 and EGSnrc Monte Carlo codes in order to determine an applicator-specific absorbed dose to water at the treatment surface from the measured air-kerma rate. Additionally

  3. Poster — Thur Eve — 41: Considerations for Patients with Permanently Implant Radioactive Sources Requiring Unrelated Surgery

    SciTech Connect

    Basran, P. S; Beckham, WA; Baxter, P

    2014-08-15

    Permanent implant of sealed radioactive sources is an effective technique for treating cancer. Typically, the radioactive sources are implanted in and near the disease, depositing dose locally over several months. There may be instances where these patients must undergo unrelated surgical procedures when the radioactive material remains active enough to pose risks. This work explores these risks, discusses strategies to mitigate those risks, and describes a case study for a permanent I-125 prostate brachytherapy implant patient who developed colo-rectal cancer and required surgery 6 months after brachytherapy. The first consideration is identifying the risk from unwarranted radiation to the patient and staff before, during, and after the surgical procedure. The second is identifying the risk the surgical procedure may have on the efficacy of the brachytherapy implant. Finally, there are considerations for controlling for radioactive substances from a regulatory perspective. After these risks are defined, strategies to mitigate those risks are considered. These strategies may include applying the concepts of ALARA, the use of protective equipment and developing a best practice strategy with the operating room team. We summarize this experience with some guidelines: If the surgical procedure is near (ex: 5 cm) of the implant; and, the surgical intervention may dislodge radioisotopes enough to compromise treatment or introduces radiation safety risks; and, the radioisotope has not sufficiently decayed to background levels; and, the surgery cannot be postponed, then a detailed analysis of risk is advised.

  4. Fast GPU-based Monte Carlo simulations for LDR prostate brachytherapy.

    PubMed

    Bonenfant, Éric; Magnoux, Vincent; Hissoiny, Sami; Ozell, Benoît; Beaulieu, Luc; Després, Philippe

    2015-07-07

    The aim of this study was to evaluate the potential of bGPUMCD, a Monte Carlo algorithm executed on Graphics Processing Units (GPUs), for fast dose calculations in permanent prostate implant dosimetry. It also aimed to validate a low dose rate brachytherapy source in terms of TG-43 metrics and to use this source to compute dose distributions for permanent prostate implant in very short times. The physics of bGPUMCD was reviewed and extended to include Rayleigh scattering and fluorescence from photoelectric interactions for all materials involved. The radial and anisotropy functions were obtained for the Nucletron SelectSeed in TG-43 conditions. These functions were compared to those found in the MD Anderson Imaging and Radiation Oncology Core brachytherapy source registry which are considered the TG-43 reference values. After appropriate calibration of the source, permanent prostate implant dose distributions were calculated for four patients and compared to an already validated Geant4 algorithm. The radial function calculated from bGPUMCD showed excellent agreement (differences within 1.3%) with TG-43 accepted values. The anisotropy functions at r = 1 cm and r = 4 cm were within 2% of TG-43 values for angles over 17.5°. For permanent prostate implants, Monte Carlo-based dose distributions with a statistical uncertainty of 1% or less for the target volume were obtained in 30 s or less for 1 × 1 × 1 mm(3) calculation grids. Dosimetric indices were very similar (within 2.7%) to those obtained with a validated, independent Monte Carlo code (Geant4) performing the calculations for the same cases in a much longer time (tens of minutes to more than a hour). bGPUMCD is a promising code that lets envision the use of Monte Carlo techniques in a clinical environment, with sub-minute execution times on a standard workstation. Future work will explore the use of this code with an inverse planning method to provide a complete Monte Carlo-based planning solution.

  5. Fast GPU-based Monte Carlo simulations for LDR prostate brachytherapy

    NASA Astrophysics Data System (ADS)

    Bonenfant, Éric; Magnoux, Vincent; Hissoiny, Sami; Ozell, Benoît; Beaulieu, Luc; Després, Philippe

    2015-07-01

    The aim of this study was to evaluate the potential of bGPUMCD, a Monte Carlo algorithm executed on Graphics Processing Units (GPUs), for fast dose calculations in permanent prostate implant dosimetry. It also aimed to validate a low dose rate brachytherapy source in terms of TG-43 metrics and to use this source to compute dose distributions for permanent prostate implant in very short times. The physics of bGPUMCD was reviewed and extended to include Rayleigh scattering and fluorescence from photoelectric interactions for all materials involved. The radial and anisotropy functions were obtained for the Nucletron SelectSeed in TG-43 conditions. These functions were compared to those found in the MD Anderson Imaging and Radiation Oncology Core brachytherapy source registry which are considered the TG-43 reference values. After appropriate calibration of the source, permanent prostate implant dose distributions were calculated for four patients and compared to an already validated Geant4 algorithm. The radial function calculated from bGPUMCD showed excellent agreement (differences within 1.3%) with TG-43 accepted values. The anisotropy functions at r = 1 cm and r = 4 cm were within 2% of TG-43 values for angles over 17.5°. For permanent prostate implants, Monte Carlo-based dose distributions with a statistical uncertainty of 1% or less for the target volume were obtained in 30 s or less for 1 × 1 × 1 mm3 calculation grids. Dosimetric indices were very similar (within 2.7%) to those obtained with a validated, independent Monte Carlo code (Geant4) performing the calculations for the same cases in a much longer time (tens of minutes to more than a hour). bGPUMCD is a promising code that lets envision the use of Monte Carlo techniques in a clinical environment, with sub-minute execution times on a standard workstation. Future work will explore the use of this code with an inverse planning method to provide a complete Monte Carlo-based planning solution.

  6. Improving photoacoustic imaging contrast of brachytherapy seeds

    NASA Astrophysics Data System (ADS)

    Pan, Leo; Baghani, Ali; Rohling, Robert; Abolmaesumi, Purang; Salcudean, Septimiu; Tang, Shuo

    2013-03-01

    Prostate brachytherapy is a form of radiotherapy for treating prostate cancer where the radiation sources are seeds inserted into the prostate. Accurate localization of seeds during prostate brachytherapy is essential to the success of intraoperative treatment planning. The current standard modality used in intraoperative seeds localization is transrectal ultrasound. Transrectal ultrasound, however, suffers in image quality due to several factors such speckle, shadowing, and off-axis seed orientation. Photoacoustic imaging, based on the photoacoustic phenomenon, is an emerging imaging modality. The contrast generating mechanism in photoacoustic imaging is optical absorption that is fundamentally different from conventional B-mode ultrasound which depicts changes in acoustic impedance. A photoacoustic imaging system is developed using a commercial ultrasound system. To improve imaging contrast and depth penetration, absorption enhancing coating is applied to the seeds. In comparison to bare seeds, approximately 18.5 dB increase in signal-to-noise ratio as well as a doubling of imaging depth are achieved. Our results demonstrate that the coating of the seeds can further improve the discernibility of the seeds.

  7. Adjuvant brachytherapy in the treatment of soft-tissue sarcomas.

    PubMed

    Crownover, R L; Marks, K E

    1999-06-01

    For many patients with STS, administering adjuvant radiation treatments in the form of interstitial brachytherapy provides an excellent alternative to a protracted course of EBRT. Ideal patients are those with intermediate- or high-grade tumors amenable to en bloc resection. Attractive features of this approach include an untainted pathologic specimen, expeditious completion of treatment, reduction in wound complications, and improved functional outcome. Brachytherapy can permit definitive reirradiation by tightly localizing the high dose radiation exposure. It is also useful in patients who are known to have or be at high risk of metastatic disease, for whom the rapid completion of local treatment allows systemic therapy to begin quickly. Introduction of HDR techniques has shifted the delivery of brachytherapy from inpatient solitary confinement to an outpatient setting. Early reports using HDR brachytherapy for treatment of adult and pediatric STS are quite encouraging. The clinical equivalence between hyperfractionated HDR schedules and traditional LDR techniques is gaining acceptance.

  8. Brachytherapy in India – a long road ahead

    PubMed Central

    Mahantshetty, Umesh; Shrivastava, Shyamkishore

    2014-01-01

    Brachytherapy can play a very important role in the definitive cure by radiation therapy in India. However, except for in a handful of centres, the majority of hospitals use it only for intracavitary treatment. The most probable reasons for such are the lack of logistical resources in terms of trained personal and supporting staff, rather than lack of radiotherapy machines and equipment. In this article, the authors look into the various aspects of brachytherapy in India: from its beginning to present days. The authors point out the resources available, shortcomings, and some possible solutions to make use of brachytherapy more popular and effective. Apart from presenting a picture of the present scenario, the article pays attention to the positive signs of brachytherapy becoming more popular in the near future. PMID:25337139

  9. Patient release criteria for low dose rate brachytherapy implants.

    PubMed

    Boyce, Dale E; Sheetz, Michael A

    2013-04-01

    A lack of consensus regarding a model governing the release of patients following sealed source brachytherapy has led to a set of patient release policies that vary from institution to institution. The U.S. Nuclear Regulatory Commission has issued regulatory guidance on patient release in NUREG 1556, Volume 9, Rev. 2, Appendix U, which allows calculation of release limits following implant brachytherapy. While the formalism presented in NUREG is meaningful for the calculation of release limits in the context of relatively high energy gamma emitters, it does not estimate accurately the effective dose equivalent for the common low dose rate brachytherapy sources Cs, I, and Pd. NUREG 1556 states that patient release may be based on patient-specific calculations as long as the calculation is documented. This work is intended to provide a format for patient-specific calculations to be used for the consideration of patients' release following the implantation of certain low dose rate brachytherapy isotopes.

  10. Image-Based Brachytherapy for the Treatment of Cervical Cancer

    SciTech Connect

    Harkenrider, Matthew M. Alite, Fiori; Silva, Scott R.; Small, William

    2015-07-15

    Cervical cancer is a disease that requires considerable multidisciplinary coordination of care and labor in order to maximize tumor control and survival while minimizing treatment-related toxicity. As with external beam radiation therapy, the use of advanced imaging and 3-dimensional treatment planning has generated a paradigm shift in the delivery of brachytherapy for the treatment of cervical cancer. The use of image-based brachytherapy, most commonly with magnetic resonance imaging (MRI), requires additional attention and effort by the treating physician to prescribe dose to the proper volume and account for adjacent organs at risk. This represents a dramatic change from the classic Manchester approach of orthogonal radiographic images and prescribing dose to point A. We reviewed the history and currently evolving data and recommendations for the clinical use of image-based brachytherapy with an emphasis on MRI-based brachytherapy.

  11. Electromagnetic tracking for treatment verification in interstitial brachytherapy

    PubMed Central

    Kellermeier, Markus; Tanderup, Kari

    2016-01-01

    Electromagnetic tracking (EMT) is used in several medical fields to determine the position and orientation of dedicated sensors, e.g., attached to surgical tools. Recently, EMT has been introduced to brachytherapy for implant reconstruction and error detection. The manuscript briefly summarizes the main issues of EMT and error detection in brachytherapy. The potential and complementarity of EMT as treatment verification technology will be discussed in relation to in vivo dosimetry and imaging. PMID:27895688

  12. [Edge effect and late thrombosis -- inevitable complications of vascular brachytherapy?].

    PubMed

    Schiele, T M; Staber, L; Kantlehner, R; Pöllinger, B; Dühmke, E; Theisen, K; Klauss, V

    2002-11-01

    Restenosis is the limiting entity after percutaneous coronary angioplasty. Vascular brachytherapy for the treatment of in-stent restenosis has been shown to reduce the repeat restenosis rate and the incidence of major adverse events in several randomized trials. Besides the beneficial effects, brachytherapy yielded some unwanted side effects. The development of new stenoses at the edges of the target lesion treated with radiation is termed edge effect. It occurs after afterloading brachytherapy as well as after implantation of radioactive stents. It is characterized by extensive intimal hyperplasia and negative remodeling. As contributing factors the axial dose fall-off, inherent to all radioactive sources, and the application of vessel wall trauma by angioplasty have been identified. The combination of both factors, by insufficient overlap of the radiation length over the injured vessel segment, has been referred to as geographic miss. It has been shown to be associated with a very high incidence of the edge effect. Avoidance of geographic miss is strongly recommended in vascular brachytherapy procedures. Late thrombosis after vascular brachytherapy is of multifactorial origin. It comprises platelet recruitment, fibrin deposition, disturbed vasomotion, non-healing dissection and stent malapposition predisposing to turbulent blood flow. The strongest predictors for late thrombosis are premature discontinuation of antiplatelet therapy and implantation of new stents during the brachytherapy procedure. With a consequent and prolonged antiplatelet therapy, the incidence of late thrombosis has been reduced to placebo levels. Edge effect and late thrombosis represent unwanted side effects of vascular brachytherapy. By means of a thorough treatment planning and prolonged antiplatelet therapy their incidences can be largely reduced. With regard to the very favorable net effect, they do not constitute relevant limitations of vascular brachytherapy.

  13. Dosimetric characteristics of a new unit for electronic skin brachytherapy.

    PubMed

    Garcia-Martinez, Teresa; Chan, Jan-Pieter; Perez-Calatayud, Jose; Ballester, Facundo

    2014-03-01

    Brachytherapy with radioactive high dose rate (HDR) (192)Ir source is applied to small skin cancer lesions, using surface applicators, i.e. Leipzig or Valencia type. New developments in the field of radiotherapy for skin cancer include electronic brachytherapy. This technique involves the placement of an HDR X-ray source close to the skin, therefore combining the benefits of brachytherapy with the reduced shielding requirements and targeted energy of low energy X-rays. Recently, the Esteya(®) Electronic Brachytherapy System (Esteya EBS, Elekta AB-Nucletron, Stockholm, Sweden) has been developed specifically for HDR brachytherapy treatment of surface lesions. The system provides radionuclide free HDR brachytherapy by means of a small 69.5 kV X-ray source. The purpose of this study is to obtain the dosimetric characterization required for clinical implementation, providing the detailed methodology to perform the commissioning. Flatness, symmetry and penumbra, percentage of depth dose (PDD), kV stability, HVL, output, spectrum, linearity, and leakage have been evaluated for a set of applicators (from 10 mm to 30 mm in diameter). Flatness and symmetry resulted better than 5% with around 1 mm of penumbra. The depth dose gradient is about 7%/mm. A kV value of 68.4 ± 1.0 kV (k = 1) was obtained, in good agreement with manufacturer data (69.5 kV). HVL was 1.85 mm Al. Dose rate for a typical 6 Gy to 7 Gy prescription resulted about 3.3 Gy/min and the leakage value was < 100 µGy/min. The new Esteya(®) Electronic Brachytherapy System presents excellent flatness and penumbra as with the Valencia applicator case, combined with an improved PDD, allowing treatment of lesions of up to a depth of 5 mm in combination with reduced treatment duration. The Esteya unit allows HDR brachytherapy superficial treatment within a minimally shielded environment due its low energy.

  14. Liquids with permanent porosity

    NASA Astrophysics Data System (ADS)

    Giri, Nicola; Del Pópolo, Mario G.; Melaugh, Gavin; Greenaway, Rebecca L.; Rätzke, Klaus; Koschine, Tönjes; Pison, Laure; Gomes, Margarida F. Costa; Cooper, Andrew I.; James, Stuart L.

    2015-11-01

    Porous solids such as zeolites and metal-organic frameworks are useful in molecular separation and in catalysis, but their solid nature can impose limitations. For example, liquid solvents, rather than porous solids, are the most mature technology for post-combustion capture of carbon dioxide because liquid circulation systems are more easily retrofitted to existing plants. Solid porous adsorbents offer major benefits, such as lower energy penalties in adsorption-desorption cycles, but they are difficult to implement in conventional flow processes. Materials that combine the properties of fluidity and permanent porosity could therefore offer technological advantages, but permanent porosity is not associated with conventional liquids. Here we report free-flowing liquids whose bulk properties are determined by their permanent porosity. To achieve this, we designed cage molecules that provide a well-defined pore space and that are highly soluble in solvents whose molecules are too large to enter the pores. The concentration of unoccupied cages can thus be around 500 times greater than in other molecular solutions that contain cavities, resulting in a marked change in bulk properties, such as an eightfold increase in the solubility of methane gas. Our results provide the basis for development of a new class of functional porous materials for chemical processes, and we present a one-step, multigram scale-up route for highly soluble ‘scrambled’ porous cages prepared from a mixture of commercially available reagents. The unifying design principle for these materials is the avoidance of functional groups that can penetrate into the molecular cage cavities.

  15. Permanence can be Defended.

    PubMed

    McGee, Andrew; Gardiner, Dale

    2017-03-01

    In donation after the circulatory-respiratory determination of death (DCDD), the dead donor rule requires that the donor be dead before organ procurement can proceed. Under the relevant limb of the Uniform Determination of Death Act 1981 (USA), a person is dead when the cessation of circulatory-respiratory function is 'irreversible'. Critics of current practice in DCDD have argued that the donor is not dead at the time organs are procured, and so the procurement of organs from these donors violates the dead donor rule. We offer a new argument here in defence of current DCDD practice, and, in particular, of the interpretation of the requirement of 'irreversibility' as permanence.

  16. Permanent Turbidity-Standards

    PubMed Central

    Roessler, William G.; Brewer, Carl R.

    1967-01-01

    Permanent turbidity reference standards suitable for measurement of microbial suspensions were prepared by suspending finely divided titanium dioxide in aryl sulfonamide-formaldehyde or methylstyrene resins. Turbidities of these standards, adjusted to a useful range for microbiological and immunological studies, were compared with other reference standards in use today. Tube holders for a Coleman Photonephelometer and a Nepho-Colorimeter were modified to eliminate the water well and to allow use of optically standardized 10-, 16-, or 18-mm test tubes. The standards and the tube holders have been used satisfactorily for more than 12 years. Images Fig. 5 Fig. 6 PMID:6077410

  17. The evolution of computerized treatment planning for brachytherapy: American contributions

    PubMed Central

    Rivard, Mark J.

    2014-01-01

    Purpose To outline the evolution of computerized brachytherapy treatment planning in the United States through a review of technological developments and clinical practice refinements. Material and methods A literature review was performed and interviews were conducted with six participants in the development of computerized treatment planning for brachytherapy. Results Computerized brachytherapy treatment planning software was initially developed in the Physics Departments of New York's Memorial Hospital (by Nelson, Meurk and Balter), and Houston's M. D. Anderson Hospital (by Stovall and Shalek). These public-domain programs could be used by institutions with adequate computational resources; other clinics had access to them via Memorial's and Anderson's teletype-based computational services. Commercial brachytherapy treatment planning programs designed to run on smaller computers (Prowess, ROCS, MMS), were developed in the late 1980s and early 1990s. These systems brought interactive dosimetry into the clinic and surgical theatre. Conclusions Brachytherapy treatment planning has evolved from systems of rigid implant rules to individualized pre- and intra-operative treatment plans, and post-operative dosimetric assessments. Brachytherapy dose distributions were initially calculated on public domain programs on large regionally located computers. With the progression of computer miniaturization and increase in processor speeds, proprietary software was commercially developed for microcomputers that offered increased functionality and integration with clinical practice. PMID:25097560

  18. A review of the clinical experience in pulsed dose rate brachytherapy

    PubMed Central

    Balgobind, Brian V; Koedooder, Kees; Ordoñez Zúñiga, Diego; Dávila Fajardo, Raquel; Rasch, Coen R N

    2015-01-01

    Pulsed dose rate (PDR) brachytherapy is a treatment modality that combines physical advantages of high dose rate (HDR) brachytherapy with the radiobiological advantages of low dose rate brachytherapy. The aim of this review was to describe the effective clinical use of PDR brachytherapy worldwide in different tumour locations. We found 66 articles reporting on clinical PDR brachytherapy including the treatment procedure and outcome. Moreover, PDR brachytherapy has been applied in almost all tumour sites for which brachytherapy is indicated and with good local control and low toxicity. The main advantage of PDR is, because of the small pulse sizes used, the ability to spare normal tissue. In certain cases, HDR resembles PDR brachytherapy by the use of multifractionated low-fraction dose. PMID:26290399

  19. A review of the clinical experience in pulsed dose rate brachytherapy.

    PubMed

    Balgobind, Brian V; Koedooder, Kees; Ordoñez Zúñiga, Diego; Dávila Fajardo, Raquel; Rasch, Coen R N; Pieters, Bradley R

    2015-01-01

    Pulsed dose rate (PDR) brachytherapy is a treatment modality that combines physical advantages of high dose rate (HDR) brachytherapy with the radiobiological advantages of low dose rate brachytherapy. The aim of this review was to describe the effective clinical use of PDR brachytherapy worldwide in different tumour locations. We found 66 articles reporting on clinical PDR brachytherapy including the treatment procedure and outcome. Moreover, PDR brachytherapy has been applied in almost all tumour sites for which brachytherapy is indicated and with good local control and low toxicity. The main advantage of PDR is, because of the small pulse sizes used, the ability to spare normal tissue. In certain cases, HDR resembles PDR brachytherapy by the use of multifractionated low-fraction dose.

  20. Cryogenic Permanent Magnet Undulators

    SciTech Connect

    Chavanne, J.; Lebec, G.; Penel, C.; Revol, F.; Kitegi, C.

    2010-06-23

    For an in-vacuum undulator operated at small gaps the permanent magnet material needs to be highly resistant to possible electron beam exposure. At room temperature, one generally uses Sm{sub 2}Co{sub 17} or high coercivity NdFeB magnets at the expense of a limited field performance. In a cryogenic permanent magnet undulator (CPMU), at a temperature of around 150 K, any NdFeB grade reveals a coercivity large enough to be radiation resistant. In particular, very high remanence NdFeB material can be used to build undulators with enhanced field and X-ray brilliance at high photon energy provided that the pre-baking of the undulator above 100 deg. C can be eliminated. The ESRF has developed a full scale 2 m long CPMU with a period of 18 mm. This prototype has been in operation on the ID6 test beamline since January 2008. A significant effort was put into the characterization of NdFeB material at low temperature, the development of dedicated magnetic measurement systems and cooling methods. The measured heat budget with beam is found to be larger than expected without compromising the smooth operation of the device. Leading on from this first experience, new CPMUs are currently being considered for the upgrade of the ESRF.

  1. Predictors of Metastatic Disease After Prostate Brachytherapy

    SciTech Connect

    Forsythe, Kevin; Burri, Ryan; Stone, Nelson; Stock, Richard G.

    2012-06-01

    Purpose: To identify predictors of metastatic disease after brachytherapy treatment for prostate cancer. Methods and Materials: All patients who received either brachytherapy alone (implant) or brachytherapy in combination with external beam radiation therapy for treatment of localized prostate cancer at The Mount Sinai Hospital between June 1990 and March 2007 with a minimum follow-up of 2 years were included. Univariate and multivariable analyses were performed on the following variables: risk group, Gleason score (GS), clinical T stage, pretreatment prostate-specific antigen level, post-treatment prostate-specific antigen doubling time (PSA-DT), treatment type (implant vs. implant plus external beam radiation therapy), treatment era, total biological effective dose, use of androgen deprivation therapy, age at diagnosis, and race. PSA-DT was analyzed in the following ordinate groups: 0 to 90 days, 91 to 180 days, 180 to 360 days, and greater than 360 days. Results: We included 1,887 patients in this study. Metastases developed in 47 of these patients. The 10-year freedom from distant metastasis (FFDM) rate for the entire population was 95.1%. Median follow-up was 6 years (range, 2-15 years). The only two significant predictors of metastatic disease by multivariable analyses were GS and PSA-DT (p < 0.001 for both variables). Estimated 10-year FFDM rates for GS of 6 or less, GS of 7, and GS of 8 or greater were 97.9%, 94.3%, and 76.1%, respectively (p < 0.001). Estimated FFDM rates for PSA-DT of 0 to 90 days, 91 to 180 days, 181 to 360 days, and greater than 360 days were 17.5%, 67.9%, 74%, and 94.8%, respectively (p < 0.001). Estimated 10-year FFDM rates for the low-, intermediate-, and high-risk groups were 98.6%, 96.2%, and 86.7%, respectively. A demographic shift to patients presenting with higher-grade disease in more recent years was observed. Conclusions: GS and post-treatment PSA-DT are both statistically significant independent predictors of metastatic

  2. An overview of interstitial brachytherapy and hyperthermia

    SciTech Connect

    Brandt, B.B.; Harney, J.

    1989-11-01

    Interstitial thermoradiotherapy, an experimental cancer treatment that combines interstitial radiation implants (brachytherapy) and interstitial hyperthermia, is in the early stages of investigation. In accordance with the procedure used in a current national trial protocol, a 60-minute hyperthermia treatment is administered after catheters are placed into the tumor area while the patient is under general anesthesia. This is immediately followed by loading of radioactive Iridium-192 seeds into the catheters for a defined period of time. Once the prescribed radiation dose is delivered, the radioactive sources are removed and a second, 60-minute hyperthermia treatment is administered. Clinical trials with hyperthermia in combination with radiation have increased in recent years. Nurses caring for these patients need to become more knowledgeable about this investigational therapy. This paper provides an overview of the biologic rationale for this therapy, as well as a description of the delivery method and clinical application. Specific related nursing interventions are defined in a nursing protocol.23 references.

  3. Paddle-based rotating-shield brachytherapy

    SciTech Connect

    Liu, Yunlong; Xu, Weiyu; Flynn, Ryan T.; Kim, Yusung; Bhatia, Sudershan K.; Buatti, John M.; Dadkhah, Hossein; Wu, Xiaodong

    2015-10-15

    Purpose: The authors present a novel paddle-based rotating-shield brachytherapy (P-RSBT) method, whose radiation-attenuating shields are formed with a multileaf collimator (MLC), consisting of retractable paddles, to achieve intensity modulation in high-dose-rate brachytherapy. Methods: Five cervical cancer patients using an intrauterine tandem applicator were considered to assess the potential benefit of the P-RSBT method. The P-RSBT source used was a 50 kV electronic brachytherapy source (Xoft Axxent™). The paddles can be retracted independently to form multiple emission windows around the source for radiation delivery. The MLC was assumed to be rotatable. P-RSBT treatment plans were generated using the asymmetric dose–volume optimization with smoothness control method [Liu et al., Med. Phys. 41(11), 111709 (11pp.) (2014)] with a delivery time constraint, different paddle sizes, and different rotation strides. The number of treatment fractions (fx) was assumed to be five. As brachytherapy is delivered as a boost for cervical cancer, the dose distribution for each case includes the dose from external beam radiotherapy as well, which is 45 Gy in 25 fx. The high-risk clinical target volume (HR-CTV) doses were escalated until the minimum dose to the hottest 2 cm{sup 3} (D{sub 2cm{sup 3}}) of either the rectum, sigmoid colon, or bladder reached their tolerance doses of 75, 75, and 90 Gy{sub 3}, respectively, expressed as equivalent doses in 2 Gy fractions (EQD2 with α/β = 3 Gy). Results: P-RSBT outperformed the two other RSBT delivery techniques, single-shield RSBT (S-RSBT) and dynamic-shield RSBT (D-RSBT), with a properly selected paddle size. If the paddle size was angled at 60°, the average D{sub 90} increases for the delivery plans by P-RSBT on the five cases, compared to S-RSBT, were 2.2, 8.3, 12.6, 11.9, and 9.1 Gy{sub 10}, respectively, with delivery times of 10, 15, 20, 25, and 30 min/fx. The increases in HR-CTV D{sub 90}, compared to D-RSBT, were 16

  4. Paddle-based rotating-shield brachytherapy

    PubMed Central

    Liu, Yunlong; Flynn, Ryan T.; Kim, Yusung; Dadkhah, Hossein; Bhatia, Sudershan K.; Buatti, John M.; Xu, Weiyu; Wu, Xiaodong

    2015-01-01

    Purpose: The authors present a novel paddle-based rotating-shield brachytherapy (P-RSBT) method, whose radiation-attenuating shields are formed with a multileaf collimator (MLC), consisting of retractable paddles, to achieve intensity modulation in high-dose-rate brachytherapy. Methods: Five cervical cancer patients using an intrauterine tandem applicator were considered to assess the potential benefit of the P-RSBT method. The P-RSBT source used was a 50 kV electronic brachytherapy source (Xoft Axxent™). The paddles can be retracted independently to form multiple emission windows around the source for radiation delivery. The MLC was assumed to be rotatable. P-RSBT treatment plans were generated using the asymmetric dose–volume optimization with smoothness control method [Liu et al., Med. Phys. 41(11), 111709 (11pp.) (2014)] with a delivery time constraint, different paddle sizes, and different rotation strides. The number of treatment fractions (fx) was assumed to be five. As brachytherapy is delivered as a boost for cervical cancer, the dose distribution for each case includes the dose from external beam radiotherapy as well, which is 45 Gy in 25 fx. The high-risk clinical target volume (HR-CTV) doses were escalated until the minimum dose to the hottest 2 cm3 (D2cm3) of either the rectum, sigmoid colon, or bladder reached their tolerance doses of 75, 75, and 90 Gy3, respectively, expressed as equivalent doses in 2 Gy fractions (EQD2 with α/β = 3 Gy). Results: P-RSBT outperformed the two other RSBT delivery techniques, single-shield RSBT (S-RSBT) and dynamic-shield RSBT (D-RSBT), with a properly selected paddle size. If the paddle size was angled at 60°, the average D90 increases for the delivery plans by P-RSBT on the five cases, compared to S-RSBT, were 2.2, 8.3, 12.6, 11.9, and 9.1 Gy10, respectively, with delivery times of 10, 15, 20, 25, and 30 min/fx. The increases in HR-CTV D90, compared to D-RSBT, were 16.6, 12.9, 7.2, 3.7, and 1.7 Gy10

  5. Harmony search optimization for HDR prostate brachytherapy

    NASA Astrophysics Data System (ADS)

    Panchal, Aditya

    In high dose-rate (HDR) prostate brachytherapy, multiple catheters are inserted interstitially into the target volume. The process of treating the prostate involves calculating and determining the best dose distribution to the target and organs-at-risk by means of optimizing the time that the radioactive source dwells at specified positions within the catheters. It is the goal of this work to investigate the use of a new optimization algorithm, known as Harmony Search, in order to optimize dwell times for HDR prostate brachytherapy. The new algorithm was tested on 9 different patients and also compared with the genetic algorithm. Simulations were performed to determine the optimal value of the Harmony Search parameters. Finally, multithreading of the simulation was examined to determine potential benefits. First, a simulation environment was created using the Python programming language and the wxPython graphical interface toolkit, which was necessary to run repeated optimizations. DICOM RT data from Varian BrachyVision was parsed and used to obtain patient anatomy and HDR catheter information. Once the structures were indexed, the volume of each structure was determined and compared to the original volume calculated in BrachyVision for validation. Dose was calculated using the AAPM TG-43 point source model of the GammaMed 192Ir HDR source and was validated against Varian BrachyVision. A DVH-based objective function was created and used for the optimization simulation. Harmony Search and the genetic algorithm were implemented as optimization algorithms for the simulation and were compared against each other. The optimal values for Harmony Search parameters (Harmony Memory Size [HMS], Harmony Memory Considering Rate [HMCR], and Pitch Adjusting Rate [PAR]) were also determined. Lastly, the simulation was modified to use multiple threads of execution in order to achieve faster computational times. Experimental results show that the volume calculation that was

  6. Calibration of Photon Sources for Brachytherapy

    NASA Astrophysics Data System (ADS)

    Rijnders, Alex

    Source calibration has to be considered an essential part of the quality assurance program in a brachytherapy department. Not only it will ensure that the source strength value used for dose calculation agrees within some predetermined limits to the value stated on the source certificate, but also it will ensure traceability to international standards. At present calibration is most often still given in terms of reference air kerma rate, although calibration in terms of absorbed dose to water would be closer to the users interest. It can be expected that in a near future several standard laboratories will be able to offer this latter service, and dosimetry protocols will have to be adapted in this way. In-air measurement using ionization chambers (e.g. a Baldwin—Farmer ionization chamber for 192Ir high dose rate HDR or pulsed dose rate PDR sources) is still considered the method of choice for high energy source calibration, but because of their ease of use and reliability well type chambers are becoming more popular and are nowadays often recommended as the standard equipment. For low energy sources well type chambers are in practice the only equipment available for calibration. Care should be taken that the chamber is calibrated at the standard laboratory for the same source type and model as used in the clinic, and using the same measurement conditions and setup. Several standard laboratories have difficulties to provide these calibration facilities, especially for the low energy seed sources (125I and 103Pd). Should a user not be able to obtain properly calibrated equipment to verify the brachytherapy sources used in his department, then at least for sources that are replaced on a regular basis, a consistency check program should be set up to ensure a minimal level of quality control before these sources are used for patient treatment.

  7. Optimisation techniques in vaginal cuff brachytherapy.

    PubMed

    Tuncel, N; Garipagaoglu, M; Kizildag, A U; Andic, F; Toy, A

    2009-11-01

    The aim of this study was to explore whether an in-house dosimetry protocol and optimisation method are able to produce a homogeneous dose distribution in the target volume, and how often optimisation is required in vaginal cuff brachytherapy. Treatment planning was carried out for 109 fractions in 33 patients who underwent high dose rate iridium-192 (Ir(192)) brachytherapy using Fletcher ovoids. Dose prescription and normalisation were performed to catheter-oriented lateral dose points (dps) within a range of 90-110% of the prescribed dose. The in-house vaginal apex point (Vk), alternative vaginal apex point (Vk'), International Commission on Radiation Units and Measurements (ICRU) rectal point (Rg) and bladder point (Bl) doses were calculated. Time-position optimisations were made considering dps, Vk and Rg doses. Keeping the Vk dose higher than 95% and the Rg dose less than 85% of the prescribed dose was intended. Target dose homogeneity, optimisation frequency and the relationship between prescribed dose, Vk, Vk', Rg and ovoid diameter were investigated. The mean target dose was 99+/-7.4% of the prescription dose. Optimisation was required in 92 out of 109 (83%) fractions. Ovoid diameter had a significant effect on Rg (p = 0.002), Vk (p = 0.018), Vk' (p = 0.034), minimum dps (p = 0.021) and maximum dps (p<0.001). Rg, Vk and Vk' doses with 2.5 cm diameter ovoids were significantly higher than with 2 cm and 1.5 cm ovoids. Catheter-oriented dose point normalisation provided a homogeneous dose distribution with a 99+/-7.4% mean dose within the target volume, requiring time-position optimisation.

  8. Online gamma-camera imaging of 103Pd seeds (OGIPS) for permanent breast seed implantation

    NASA Astrophysics Data System (ADS)

    Ravi, Ananth; Caldwell, Curtis B.; Keller, Brian M.; Reznik, Alla; Pignol, Jean-Philippe

    2007-09-01

    Permanent brachytherapy seed implantation is being investigated as a mode of accelerated partial breast irradiation for early stage breast cancer patients. Currently, the seeds are poorly visualized during the procedure making it difficult to perform a real-time correction of the implantation if required. The objective was to determine if a customized gamma-camera can accurately localize the seeds during implantation. Monte Carlo simulations of a CZT based gamma-camera were used to assess whether images of suitable quality could be derived by detecting the 21 keV photons emitted from 74 MBq 103Pd brachytherapy seeds. A hexagonal parallel hole collimator with a hole length of 38 mm, hole diameter of 1.2 mm and 0.2 mm septa, was modeled. The design of the gamma-camera was evaluated on a realistic model of the breast and three layers of the seed distribution (55 seeds) based on a pre-implantation CT treatment plan. The Monte Carlo simulations showed that the gamma-camera was able to localize the seeds with a maximum error of 2.0 mm, using only two views and 20 s of imaging. A gamma-camera can potentially be used as an intra-procedural image guidance system for quality assurance for permanent breast seed implantation.

  9. A study of optimization techniques in HDR brachytherapy for the prostate

    NASA Astrophysics Data System (ADS)

    Pokharel, Ghana Shyam

    Several studies carried out thus far are in favor of dose escalation to the prostate gland to have better local control of the disease. But optimal way of delivery of higher doses of radiation therapy to the prostate without hurting neighboring critical structures is still debatable. In this study, we proposed that real time high dose rate (HDR) brachytherapy with highly efficient and effective optimization could be an alternative means of precise delivery of such higher doses. This approach of delivery eliminates the critical issues such as treatment setup uncertainties and target localization as in external beam radiation therapy. Likewise, dosimetry in HDR brachytherapy is not influenced by organ edema and potential source migration as in permanent interstitial implants. Moreover, the recent report of radiobiological parameters further strengthen the argument of using hypofractionated HDR brachytherapy for the management of prostate cancer. Firstly, we studied the essential features and requirements of real time HDR brachytherapy treatment planning system. Automating catheter reconstruction with fast editing tools, fast yet accurate dose engine, robust and fast optimization and evaluation engine are some of the essential requirements for such procedures. Moreover, in most of the cases we performed, treatment plan optimization took significant amount of time of overall procedure. So, making treatment plan optimization automatic or semi-automatic with sufficient speed and accuracy was the goal of the remaining part of the project. Secondly, we studied the role of optimization function and constraints in overall quality of optimized plan. We have studied the gradient based deterministic algorithm with dose volume histogram (DVH) and more conventional variance based objective functions for optimization. In this optimization strategy, the relative weight of particular objective in aggregate objective function signifies its importance with respect to other objectives

  10. Brachytherapy attains abscopal effects when combined with immunostimulatory monoclonal antibodies.

    PubMed

    Rodriguez-Ruiz, María E; Rodriguez, Inmaculada; Barbes, Benigno; Mayorga, Lina; Sanchez-Paulete, Alfonso Rodriguez; Ponz-Sarvise, Mariano; Pérez-Gracia, José Luis; Melero, Ignacio

    2017-08-21

    Preclinical and clinical evidence indicate that the proimmune effects of radiotherapy can be synergistically augmented with immunostimulatory monoclonal antibodies (mAb) to act both on irradiated tumor lesions and on tumors at distant, nonirradiated sites. We have recently reported that external beam radiotherapy achieves abscopal effects when combined with antagonist anti-PD1 mAbs and agonist anti-CD137 (4-1BB) mAbs. The goal of this work is to study the abscopal effects of radiotherapy instigated by brachytherapy techniques. Mice bearing a subcutaneous colorectal carcinoma, MC38 (colorectal cancer), in both flanks were randomly assigned to receive brachytherapy or not (8 Gy × three fractions) to only one of the two grafted tumors, in combination with intraperitoneal immunostimulatory monoclonal antibodies (anti-PD1, anti-CD137, and/or their respective isotype controls). To study the abscopal effects of brachytherapy, we established an experimental set up that permits irradiation of mouse tumors sparing a distant site resembling metastasis. Such second nonirradiated tumor was used as indicator of abscopal effect. Tumor size was monitored every 2 days. Abscopal effects on distant nonirradiated subcutaneous tumor lesions of transplanted MC38-derived tumors only took place when brachytherapy was combined with immunostimulatory anti-PD1 and/or anti-CD137 mAbs. Our results demonstrate that immunotherapy-potentiated abscopal effects can be attained by brachytherapy. Accordingly, immunotherapy plus brachytherapy combinations are suitable for clinical translation. Copyright © 2017 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  11. A modified dose calculation formalism for electronic brachytherapy sources.

    PubMed

    DeWerd, Larry A; Culberson, Wesley S; Micka, John A; Simiele, Samantha J

    2015-01-01

    To propose a modification of the current dose calculation formalism introduced in the Task Group No. 43 Report (TG-43) to accommodate an air-kerma rate standard for electronic brachytherapy sources as an alternative to an air-kerma strength standard. Electronic brachytherapy sources are miniature x-ray tubes emitting low energies with high-dose-rates. The National Institute of Standards and Technology (NIST) has introduced a new primary air-kerma rate standard for one of these sources, in contrast to air-kerma strength. A modification of the TG-43 protocol for calculation of dose-rate distributions around electronic brachytherapy sources including sources in an applicator is presented. It cannot be assumed that the perturbations from sources in an applicator are negligible, and thus, the applicator is incorporated in the formalism. The modified protocol mimics the fundamental methodology of the original TG-43 formalism, but now incorporates the new NIST-traceable source strength metric of air-kerma rate at 50 cm and introduces a new subscript, i, to denote the presence of an applicator used in treatment delivery. Applications of electronic brachytherapy sources for surface brachytherapy are not addressed in this Technical Note since they are well documented in other publications. A modification of the AAPM TG-43 protocol has been developed to accommodate an air-kerma rate standard for electronic brachytherapy sources as an alternative to an air-kerma strength standard. The modified TG-43 formalism allows dose calculations to be performed using a new NIST-traceable source strength metric and introduces the concept of applicator-specific formalism parameters denoted with subscript, i. Copyright © 2015 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  12. Methods for prostate stabilization during transperineal LDR brachytherapy

    NASA Astrophysics Data System (ADS)

    Podder, Tarun; Sherman, Jason; Rubens, Deborah; Messing, Edward; Strang, John; Ng, Wan-Sing; Yu, Yan

    2008-03-01

    In traditional prostate brachytherapy procedures for a low-dose-rate (LDR) radiation seed implant, stabilizing needles are first inserted to provide some rigidity and support to the prostate. Ideally this will provide better seed placement and an overall improved treatment. However, there is much speculation regarding the effectiveness of using regular brachytherapy needles as stabilizers. In this study, we explored the efficacy of two types of needle geometries (regular brachytherapy needle and hooked needle) and several clinically feasible configurations of the stabilization needles. To understand and assess the prostate movement during seed implantation, we collected in vivo data from patients during actual brachytherapy procedures. In vitro experimentation with tissue-equivalent phantoms allowed us to further understand the mechanics behind prostate stabilization. We observed superior stabilization with the hooked needles compared to the regular brachytherapy needles (more than 40% in bilateral parallel needle configuration). Prostate movement was also reduced significantly when regular brachytherapy needles were in an angulated configuration as compared to the parallel configuration (more than 60%). When the hooked needles were angulated for stabilization, further reduction in prostate displacement was observed. In general, for convenience of dosimetric planning and to avoid needle collision, all needles are desired to be in a parallel configuration. In this configuration, hooked needles provide improved stabilization of the prostate. On the other hand, both regular and hooked needles appear to be equally effective in reducing prostate movement when they are in angulated configurations, which will be useful in seed implantation using a robotic system. We have developed nonlinear spring-damper model for the prostate movement which can be used for adapting dosimetric planning during brachytherapy as well as for developing more realistic haptic devices and

  13. Achieving permanency for LGBTQ youth.

    PubMed

    Jacobs, Jill; Freundlich, Madelyn

    2006-01-01

    This article brings together two significant efforts in the child welfare field: achieving permanence for youth in out-of-home care and meeting the needs of lesbian, gay, bisexual, transgender and questioning (LGBTQ) youth. During the past several years, a national movement has taken place to assure all children and youth have a permanent family connection before leaving the child welfare system; however, LGBTQ youth are not routinely included in the permanency discussions. At the same time, efforts in addressing the needs of LGBTQ youth have increased, but permanency is rarely mentioned as a need. This article offers models of permanence and practices to facilitate permanence with LGBTQ youth and their families. It also offers a youth-driven, individualized process, using youth development principles to achieve relational, physical, and legal permanence. Reunification efforts are discussed, including services, supports, and education required for youth to return to their family of origin. For those who cannot return home, other family resources are explored. The article also discusses cultural issues as they affect permanence for LGBTQ youth, and, finally, addresses the need for ongoing support services to sustain and support permanency.

  14. Quantitative radiommunoassay for DNA-binding antibodies. [Iodine 131, Iodine 125

    SciTech Connect

    Smith, L.H.; Guyer, R.L.; Minami, R.M.; Teplitz, R.L.

    1981-09-01

    A radioimmunoassay (RIA) is described for the measurement of serum immunoglobulins capable of binding to double-standard or single-standard DNA. DNA attached to Sephadex G-50 by ultraviolet radiation was used as a solid- phase immunoabsorbent for DNA-binding proteins from serum. Goat anti-human (GAH) IgG (/sup 125/I-labeled) were used to detect the human immunoglobulins bound onto the washed DNA-Sephadex. The quantities of immunoglobulins bound were determined by comparison with a standard curve constructed by dilution of a plasma from an systemic lupus erythematosus (SLE) patient containing known amounts of bound, DNA-specific IgM and IgG. Another RIA was employed for measuring levels of IgG and IgM. In combination with measurements of the total serum IgM and IgG, the RIA allowed for the determination of the fraction of the total serum IgM or IgG that was specific for double- or single-standard DNA. For a pool of normal human sera the quantities were as follows: 0.04% of the total IgM and 0.001% of the total IgG bound double-standard DNA; 0.22% of the total IgM and 0.05% of the total IgG bound single-stranded DNA. This capability is important because information regarding the quantitative measurement of antibodies to DNA and their class determination may be of significance in monitoring the status of subjects with SLE.

  15. Quantitative analysis of myocardial kinetics of 15-p-(iodine-125) iodophenylpentadecanoic acid

    SciTech Connect

    DeGrado, T.R.; Holden, J.E.; Ng, C.K.; Raffel, D.M.; Gatley, S.J.

    1989-07-01

    Myocardial extraction and the characteristic tissue clearance of radioactivity following bolus injections of a radioiodinated (/sup 125/I) long chain fatty acid (LCFA) analog 15-p-iodophenylpentadecanoic acid (IPPA) were examined in the isolated perfused working rat heart. Radioactivity remaining in the heart was monitored with external scintillation probes. A compartmental model which included nonesterified tracer, catabolite, and complex lipid compartments successfully fitted tissue time-radioactivity residue curves, and gave a value for the rate of IPPA oxidation 1.8 times that obtained from steady-state release of tritiated water from labeled palmitic acid. The technique was sensitive to the impairment of LCFA oxidation in hearts of animals treated with the carnitine palmitoyltransferase I inhibitor, 2(5(4-chlorophenyl)pentyl)oxirane-2-carboxylate (POCA). IPPA or similar modified fatty acids may be better than /sup 11/C-labeled physiological fatty acids such as palmitate in this type of study, because efflux of unoxidized tracer and catabolite(s) from the heart are kinetically more distinct, and their contributions to the early data can be reliably separated. This technique may be suitable for extension to in vivo measurements with position tomography and appropriate modified fatty acids.

  16. Dual isotope study of iodine-125 and indium-111-labeled antibody in athymic mice

    SciTech Connect

    Carney, P.L.; Rogers, P.E.; Johnson, D.K. )

    1989-03-01

    Monoclonal antibody B72.3 was coupled to a benzylisothiocyanate derivative of diethylenetriaminepentaacetic acid (DTPA). The maximum substitution achievable without loss of immunoreactivity was three DTPA groups per immunoglobulin molecule. The resulting conjugate was labeled with {sup 111}In by brief incubation with {sup 111}InCl{sub 3}, giving a mean radiochemical yield of {sup 111}In-labeled antibody of 96%. The ({sup 111}In)B72.3 preparation was mixed with an ({sup 125}I) B72.3 preparation, obtained by the chloramine-T method, and the mixture administered to athymic mice bearing subcutaneous LS174T colon carcinoma xenografts. There were no significant differences (p greater than 0.1) in the biodistributions of the two labels at 1, 2, 5, and 7 days postinjection. These results are contrasted with prior studies showing elevated levels of {sup 111}In in liver, spleen, and kidneys using B72.3-DTPA conjugates prepared via the bicyclic anhydride. It is concluded that protein cross-linking and/or the formation of unstable chelate sites in anhydride coupled conjugates underlie these disparities.

  17. Diagnostic methods for deep vein thrombosis: venous Doppler examination, phleborheography, iodine-125 fibrinogen uptake, and phlebography

    SciTech Connect

    Comerota, A.J.; White, J.V.; Katz, M.L.

    1985-10-08

    Since clinical diagnosis of DVT is often inaccurate, it has become accepted that an objective means of diagnosing clot in the deep venous system becomes critically important in the management of these patients. The venous Doppler examination monitors the velocity of blood flowing through a particular vein. Doppler probes in the 5 to 10 mHz range are routinely used. Respiratory variation is a normal finding due to a diminished flow signal during inspiration, followed by a progressive increase in flow signal during expiration. Characteristics of the spontaneous flow signals are the most important part of interpreting the venous Doppler examination. In addition, the response to distal or proximal compression (augmentation) adds important information to the interpretation; however, the response during any augmentation maneuver depends on the rapidity of compression, the force of compression, the quantity of blood in the veins at the time of compression, and the distance between the Doppler probe and the compression point. Phleborheography is a six-channel volumetric plethysmographic technique that monitors volume changes in the lower extremities associated with respiration and foot and calf compression.

  18. Experience with interstitial implantation of iodine 125 in the treatment of prostatic carcinoma.

    PubMed

    Sogani, P C; Whitmore, W F; Hilaris, B S; Batata, M A

    1980-01-01

    Between February 1970 and April 1977 300 patients with localized prostatic carcinoma were treated with I-125 implantation and bilateral pelvic lymphadenectomy at Memorial Sloan-Kettering Cancer Center (MSKCC). 68% had clinical Stage B (T-1 and T-2) and 32% had Stage C (T-3) neoplasms. Pelvic lymph nodes were histologically positive in 38% of the patients. Five-year survival for all patients was 73%. Five-year survival for Stage B disease was 100% and Stage C 65%. Lymph node metastases implied a poor prognosis. While 92% of patients with negative nodes survived five years, only 46% of the patients with positive nodes did so. Supplemental external radiation to pelvic and periaortic region in 28 patients with positive nodes did not improve survival or disease free interval or reduce distal or local recurrence but rather increased the incidence of radiation morbidity. The complications and morbidity as a consequence of I-125 implantation are minimal. The ultimate role of I-125 implantation in the management of localized prostatic cancer is yet to be determined. The early experience with this technique, however, suggests that it may be as effective as alternative modalities for comparable stages in terms of patient survival and may prove superior in terms of the quality of survival.

  19. Ultrasonically guided percutaneous implantation of iodine-125 seeds in pancreatic carcinoma

    SciTech Connect

    Joyce, F.; Burcharth, F.; Holm, H.H.; Stroyer, I. )

    1990-10-01

    Cancer of the pancreas is most often not diagnosed before it has reached unresectable stages. The development of effective palliative treatment for these patients and for those with recurrence after resection is clearly needed. The present study reports the results of ultrasonically guided percutaneous implantation of {sup 125}I seeds in 19 patients with cancer of the pancreas. Twelve patients had further adjuvant external radiation. Despite satisfactory seed placement and delivery of the planned radiation dose in most cases, clinical improvement was lacking or only slight and short-lived. No difference in survival or palliation was observed between patients treated with seeds alone compared with patients treated with seeds and external radiation. Survival after seed implantation was short (median 140 days, range 7-401 days). Ultrasonically guided percutaneous implantation of {sup 125}I seeds cannot be recommended in the treatment of unresectable carcinoma of the pancreas.

  20. a Study of the Dosimetry of IODINE-125 Seed Interstitial Implants Using Monte Carlo Simulation Methods.

    NASA Astrophysics Data System (ADS)

    Burns, Gregory Scott

    Monte Carlo simulation methods were used to investigate the absorbed dose distribution around several preliminary source configurations and the 3M Company models 6701, 6702, and 6711 I-125 seeds in water. Simulations for the preliminary sources, all of which were structurally simpler than the seeds, were conducted to demonstrate correct behavior of the computer software. The relative dose distributions of the three seed models were found to be anisotropic, and distinct. Observed differences in the relative dose distributions of the three models are attributable to differences in seed design and photon emission spectrum. Variations in end weld thicknesses and radioactivity distributions within the seeds were found to have substantial influence on the relative dose distributions. Dosimetry estimates along the longitudinal axis of the seeds are particularly uncertain due to such variations. Finally, perturbations of the single seed dose distribution created by neighboring seeds within the implant were determined. Such perturbations are strongly dependent on the seed model used and on the separation between seeds. Simple superposition of single seed dose distributions in multiple seed implants causes overestimation of dose within seed planes. Errors may be quite large for single plane implants with small seed separations. The results of this study provide a means to reduce errors in iodine seed implant dosimetry through the use of seed design-specific two-dimensional dosimetry data, and through improved understanding of the causes of uncertainties in iodine seed relative dose distributions.

  1. Auger-electron cascades, charge potential and microdosimetry of iodine-125.

    PubMed

    Booz, J; Paretzke, H G; Pomplun, E; Olko, P

    1987-01-01

    This paper is a contribution to the microdosimetry of I-125. It shows microdosimetric spectra of individual and average disintegrations of I-125 for various target sizes and gives evidence for the relative contributions of energy-deposition events of low and high LET. It further presents information on the relative efficiencies of Auger-electrons and multiple charges in terms of local energy deposition, e.g. to model targets of DNA, and discusses their radiobiological implications, e.g. the microdosimetric understanding of the different efficiencies of specific and random incorporations of I-125. When I-125 is specifically incorporated into DNA, most of the energy deposition events are very large, e.g. above 40 keV/micron for a simulated target volume of 20 nm diameter, regardless of the number and energy of Auger electrons emitted. Therefore it is not necessary, for the discussion of the radiobiological implications, to distinguish between different classes of disintegrations. For unspecific, homogeneous incorporation of I-125 somewhere into tissue, about 20% of the dose to critical targets of 25 nm diameter is made up by disintegrations that happen to occur within these targets. When assuming that other critical targets and target structures can be neglected, this part of the dose will be equally effective as in the case of specific incorporation of I-125 into such target models. In addition, there are the normal, low-LET radiation effects from the other, 80% large fraction of the dose. With this information, for the biological systems and end points for which a short section of the elemental chromatine fiber can be taken as the relevant critical target, it is shown that the expected D37 value for homogeneous unspecific incorporation of I-125 can be estimated when the D37 for specific incorporation in DNA is known. For an example calculation, the estimated D37-value for nonspecific, homogeneous incorporation of I-125 would be about half as effective as specifically incorporated I-125. Thus, the microdosimetric data of the present work show that a high efficiency of homogeneous incorporation of I-125 into the cell nucleus is not necessarily in contradiction with the idea of I-125 disintegrations inside the DNA being the main cause of radiation action.

  2. Brachytherapy for malignancies of the vagina in the 3D era

    PubMed Central

    Glaser, Scott M.

    2015-01-01

    Vaginal cancer is an uncommon malignancy and can be either recurrent or primary. In both cases, brachytherapy places a central role in the overall treatment course. Recent technological advances have led to more advanced brachytherapy techniques, which in turn have translated to improved outcomes for patients with malignancies of the vagina. The aim of this manuscript is to outline the incorporation of modern brachytherapy into the treatment of patients with vaginal cancer including patient selection along with the role of brachytherapy in conjunction with other treatment modalities, various brachytherapy techniques, treatment planning, dose fractionation schedules, and normal tissue tolerance. PMID:26622234

  3. Utilization and Outcomes of Breast Brachytherapy in Younger Women

    PubMed Central

    Smith, Grace L; Huo, Jinhai; Giordano, Sharon H.; Hunt, Kelly K.; Buchholz, Thomas A; Smith, Benjamin D

    2015-01-01

    Background Breast brachytherapy after lumpectomy is controversial in younger patients, as effectiveness is unclear and selection criteria are debated. Methods Using MarketScan® healthcare claims data, we identified 45,884 invasive breast cancer patients (ages 18–64), treated from 2003–2010 with lumpectomy, followed by brachytherapy (n=3,134) or whole breast irradiation (WBI) (n=42,750). We stratified patients into risk groups, based on age (Age<50 vs. Age≥50) and endocrine therapy status (Endocrine− vs. Endocrine+). “Endocrine+” patients filled an endocrine therapy prescription within 1 year after lumpectomy. Pathologic hormone receptor status was not available in this dataset. In brachytherapy vs. WBI patients, utilization trends and 5-year subsequent mastectomy risks were compared. Stratified, adjusted subsequent mastectomy risks were calculated using proportional hazards regression. Results Brachytherapy utilization increased from 2003 to 2010: In patients Age<50, from 0.6% to 4.9%; patients Age≥50 from 2.2% to 11.3%; Endocrine− patients, 1.3% to 9.4%; Endocrine+ patients, 1.9% to 9.7%. Age influenced treatment selection more than endocrine status: 17% of brachytherapy patients were Age<50 vs. 32% of WBI patients (P<0.001); while 41% of brachytherapy patients were Endocrine- vs. 44% of WBI patients (P=0.003). Highest absolute 5-year subsequent mastectomy risks occurred in Endocrine−/Age<50 patients (24.4% after brachytherapy vs. 9.0% after WBI (Hazard ratio[HR]=2.18, 1.37–3.47); intermediate risks in Endocrine−/Age≥50 patients (8.6% vs. 4.9%; HR=1.76, 1.26–2.46); and lowest risks in Endocrine+ patients of any age: Endocrine+/Age<50 (5.5% vs. 4.5%; HR=1.18, 0.61–2.31); Endocrine+/Age≥50 (4.2% vs. 2.4%; HR=1.71, 1.16–2.51). Conclusion In this younger cohort, endocrine status was a valuable discriminatory factor predicting subsequent mastectomy risk after brachytherapy vs. WBI and therefore may be useful for selecting appropriate

  4. Utilization and Outcomes of Breast Brachytherapy in Younger Women

    SciTech Connect

    Smith, Grace L.; Huo, Jinhai; Giordano, Sharon H.; Hunt, Kelly K.; Buchholz, Thomas A.; Smith, Benjamin D.

    2015-09-01

    Purpose: To directly compare (1) radiation treatment utilization patterns; (2) risks of subsequent mastectomy; and (3) costs of radiation treatment in patients treated with brachytherapy versus whole-breast irradiation (WBI), in a national, contemporary cohort of women with incident breast cancer, aged 64 years and younger. Methods and Materials: Using MarketScan health care claims data, we identified 45,884 invasive breast cancer patients (aged 18-64 years), treated from 2003 to 2010 with lumpectomy, followed by brachytherapy (n=3134) or whole-breast irradiation (n=42,750). We stratified patients into risk groups according to age (Age<50 vs Age≥50) and endocrine therapy status (Endocrine− vs Endocrine+). “Endocrine+” patients filled an endocrine therapy prescription within 1 year after lumpectomy. Pathologic hormone receptor status was not available in this dataset. In brachytherapy versus WBI patients, utilization trends and 5-year subsequent mastectomy risks were compared. Stratified, adjusted subsequent mastectomy risks were calculated using proportional hazards regression. Results: Brachytherapy utilization increased from 2003 to 2010: in patients Age<50, from 0.6% to 4.9%; patients Age≥50 from 2.2% to 11.3%; Endocrine− patients, 1.3% to 9.4%; Endocrine+ patients, 1.9% to 9.7%. Age influenced treatment selection more than endocrine status: 17% of brachytherapy patients were Age<50 versus 32% of WBI patients (P<.001); whereas 41% of brachytherapy patients were Endocrine–versus 44% of WBI patients (P=.003). Highest absolute 5-year subsequent mastectomy risks occurred in Endocrine−/Age<50 patients (24.4% after brachytherapy vs 9.0% after WBI (hazard ratio [HR] 2.18, 95% confidence interval [CI] 1.37-3.47); intermediate risks in Endocrine−/Age≥50 patients (8.6% vs 4.9%; HR 1.76, 95% CI 1.26-2.46); and lowest risks in Endocrine+ patients of any age: Endocrine+/Age<50 (5.5% vs 4.5%; HR 1.18, 95% CI 0.61-2.31); Endocrine+/Age≥50 (4.2% vs 2

  5. Poster - Thur Eve - 12: Dosimetric manifestation of harmonic mode imaging for seed implant brachytherapy.

    PubMed

    Sandhu, G; Angyalfi, S; Dunscombe, P; Khan, R

    2012-07-01

    To demonstrate the dosimetric effects of observer variability in defining the prostate and critical organs, using Tissue Harmonic (H) ultrasound imaging mode for permanent seed implant brachytherapy. Images were acquired using a B -K medical 8848 probe with Brightness (B) and H mode for ten prostate brachytherapy patients. The prostate, rectum and urethra were contoured independently by five observers. The clinically used treatment plans based on B mode imaging fulfilling the dosimetric criteria were applied on these contours. Dosimetric parameters (prostate: D90, V100 and V200; rectum: V100; urethra: V140, V150 and V160) were computed using SPOT PRO™ planning system. Interobserver variability in dosimetric parameters was tested using standard deviations as percentages of means. Two-factor analysis of variances showed significant (p<0.05) interobserver variability in all dosimetric parameters for both modes. Interobserver agreement in dosimetric parameters improves in H mode due to improved interobserver consistency in contouring these organs on H mode images compared to B mode. There is no significant difference observed (paired student t test, p>0.05) in the mean values of dosimetric parameters in H and B mode for prostate and critical organs. H mode due to its better image quality helped to improve the interobserver agreement in contouring the prostate and critical organs and hence better interobserver consistency in all dosimetric parameter. Because the difference in the mean value of dosimetric parameters between two imaging modes is not statistically significant, H mode does not appear to offer any clinical advantages in terms of improving the dosimetric outcome. © 2012 American Association of Physicists in Medicine.

  6. Efficacy of brachytherapy for prostate cancer in African Americans compared with Caucasians.

    PubMed

    Barrett, William L; Kassing, William M; Shirazi, Reza

    2004-01-01

    To compare the biochemical response to prostate brachytherapy between African Americans and Caucasians in a consecutive series of patients treated at a single institution. Between July 1995 and October 2001, 173 patients were treated with permanent (125)I seed implantation alone for presumed localized adenocarcinoma of the prostate. Twelve patients were African American and their biochemical response to treatment was compared with the 161 Caucasian patients. The patients were evaluated for biochemical recurrence according to the ASTRO consensus statement and for achieving and maintaining PSA nadirs of < or = 1.0, < or = 0.5, and < or = 0.2. Median pretreatment PSA level was 8 for the African American group and 6 for the Caucasian group. Median Gleason score for each group was 6 and no patients had palpable extraprostatic disease at the time of treatment. None of the African American patients have experienced biochemical recurrence compared with 7.5% of the Caucasian patients (p=0.34). The percentage of African American patients achieving and maintaining a PSA level of < or = 1.0 was 83% compared with 89% for the Caucasian patients (p=0.61). PSA nadir of < or = 0.5 was achieved in 75% of the African American patients and 81% of the Caucasian patients (p=0.52) and 50% of the African American patients experienced PSA levels of < or = 0.2 compared with 59% of the Caucasian patients (p=0.88). African American patients with prostate cancer have in general been reported to have worse prognosis compared with Caucasians. This series suggests similar outcome between African American and Caucasian patients treated with brachytherapy for prostate cancer.

  7. egs_brachy: a versatile and fast Monte Carlo code for brachytherapy

    NASA Astrophysics Data System (ADS)

    Chamberland, Marc J. P.; Taylor, Randle E. P.; Rogers, D. W. O.; Thomson, Rowan M.

    2016-12-01

    egs_brachy is a versatile and fast Monte Carlo (MC) code for brachytherapy applications. It is based on the EGSnrc code system, enabling simulation of photons and electrons. Complex geometries are modelled using the EGSnrc C++ class library and egs_brachy includes a library of geometry models for many brachytherapy sources, in addition to eye plaques and applicators. Several simulation efficiency enhancing features are implemented in the code. egs_brachy is benchmarked by comparing TG-43 source parameters of three source models to previously published values. 3D dose distributions calculated with egs_brachy are also compared to ones obtained with the BrachyDose code. Well-defined simulations are used to characterize the effectiveness of many efficiency improving techniques, both as an indication of the usefulness of each technique and to find optimal strategies. Efficiencies and calculation times are characterized through single source simulations and simulations of idealized and typical treatments using various efficiency improving techniques. In general, egs_brachy shows agreement within uncertainties with previously published TG-43 source parameter values. 3D dose distributions from egs_brachy and BrachyDose agree at the sub-percent level. Efficiencies vary with radionuclide and source type, number of sources, phantom media, and voxel size. The combined effects of efficiency-improving techniques in egs_brachy lead to short calculation times: simulations approximating prostate and breast permanent implant (both with (2 mm)3 voxels) and eye plaque (with (1 mm)3 voxels) treatments take between 13 and 39 s, on a single 2.5 GHz Intel Xeon E5-2680 v3 processor core, to achieve 2% average statistical uncertainty on doses within the PTV. egs_brachy will be released as free and open source software to the research community.

  8. A novel approach to an automated needle insertion in brachytherapy procedures.

    PubMed

    Buzurovic, Ivan M; Salinic, Slavisa; Orio, Peter F; Nguyen, Paul L; Cormack, Robert A

    2017-07-15

    One of the most challenging phases in interstitial brachytherapy is the placement of the needles. In these medical procedures, the needles are inserted inside the tissue to guide the positioning of the radioactive sources. The low-dose-rate radioactive sources are placed inside the tissue permanently, whereas a radioactive source in the high-dose-rate brachytherapy is temporarily placed in the desired positions so that the delivery of the prescription dose to the clinical targets can be achieved. Consequently, the precise needle placement directly influences the radiation dose delivery and the treatment outcomes of patients. Any deviation from the desired position of the radioactive sources can cause a suboptimal dose distribution and inadequate tumor coverage. Therefore, it is of significant importance to develop a robust and sophisticated tool that can perform the automatic needle placement with a high level of accuracy for different medical procedures and conditions. In this study, we propose a novel concept for the automatic needle insertion using a new miniature automated robotic system. The mathematical model of this system was presented in detail, allowing the implementation of the model predictive control that can be used to govern the mechanism. The purpose of this approach was to minimize the lateral components of the generalized reactive force which is responsible for the tissue displacement and, consequently, for the needle deflection. The proposed approach was designed to predict and to compensate for the unmeasured disturbances, such as needle deflection or tissue resistance and reactive force, and it was capable of correcting them without waiting until the effect appears at the output of the system causing the needle deviation from the desired positions. The extensive simulation of the system was presented to evaluate the feasibility of the method and the parameters of interest including displacements, system errors and system responses to the change

  9. Vaginal brachytherapy for postoperative endometrial cancer: 2014 Survey of the American Brachytherapy Society.

    PubMed

    Harkenrider, Matthew M; Grover, Surbhi; Erickson, Beth A; Viswanathan, Akila N; Small, Christina; Kliethermes, Stephanie; Small, William

    2016-01-01

    Report current practice patterns for postoperative endometrial cancer emphasizing vaginal brachytherapy (VBT). A 38-item survey was e-mailed to 1,598 American Brachytherapy Society (ABS) members and 4,329 US radiation oncologists in 2014 totaling 5,710 recipients. Responses of practitioners who had delivered VBT in the previous 12 months were included in the analysis. Responses were tabulated to determine relative frequency distributions. χ(2) analysis was used to compare current results with those from the 2003 ABS survey. A total of 331 respondents initiated the VBT survey, of whom 289 (87.3%) administered VBT in the prior 12 months. Lymph node dissection and number of nodes removed influenced treatment decisions for 90.5% and 69.8%, respectively. High-dose-rate was used by 96.2%. The most common vaginal length treated was 4 cm (31.0%). Three-dimensional planning was used by 83.2% with 73.4% of those for the first fraction only. Doses to normal tissues were reported by 79.8%. About half optimized to the location of dose specification and/or normal tissues. As monotherapy, the most common prescriptions were 7 Gy for three fractions to 0.5-cm depth and 6 Gy for five fractions to the surface. As a boost, the most common prescriptions were 5 Gy for three fractions to 0.5-cm depth and 6 Gy for three fractions to the vaginal surface. Optimization points were placed at the apex and lateral vagina by 73.1%. Secondary quality assurance checks were performed by 98.9%. VBT is a common adjuvant therapy for endometrial cancer patients, most commonly with HDR. Fractionation and planning processes are variable but generally align with ABS recommendations. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  10. Percutaneous interstitial brachytherapy for adrenal metastasis: technical report

    PubMed Central

    Kishi, Kazushi; Tamura, Shinji; Mabuchi, Yasushi; Sonomura, Tetsuo; Noda, Yasutaka; Nakai, Motoki; Sato, Morio; Ino, Kazuhiko; Yamanaka, Noboru

    2012-01-01

    We developed and evaluated the feasibility of a brachytherapy technique as a safe and effective treatment for adrenal metastasis. Adapting a paravertebral insertion technique in radiofrequency ablation of adrenal tumors, we developed an interstitial brachytherapy for adrenal metastasis achievable on an outpatient basis. Under local anesthesia and under X-ray CT guidance, brachytherapy applicator needles were percutaneously inserted into the target. A treatment plan was created to eradicate the tumor while preserving normal organs including the spinal cord and kidney. We applied this interstitial brachytherapy technique to two patients: one who developed adrenal metastasis as the third recurrence of uterine cervical cancer after reirradiation, and one who developed metachronous multiple metastases from malignant melanoma. The whole procedure was completed in 2.5 hours. There were no procedure-related or radiation-related early/late complications. FDG PET-CT images at two and three months after treatment showed absence of FDG uptake, and no recurrence of the adrenal tumor was observed for over seven months until expiration, and for six months until the present, respectively. This interventional interstitial brachytherapy procedure may be useful as a safe and eradicative treatment for adrenal metastasis. PMID:22843376

  11. Prostate brachytherapy in patients with median lobe hyperplasia.

    PubMed

    Wallner, K; Smathers, S; Sutlief, S; Corman, J; Ellis, W

    2000-06-20

    Our aim was to document the technical and clinical course of prostate brachytherapy patients with radiographic evidence of median lobe hyperplasia (MLH). Eight patients with MLH were identified during our routine brachytherapy practice, representing 9% of the 87 brachytherapy patients treated during a 6-month period. No effort was made to avoid brachytherapy in patients noted to have MLH on diagnostic work-up. Cystoscopic evaluation was not routinely performed. Postimplant axial computed tomographic (CT) images of the prostate were obtained at 0.5 cm intervals. Preimplant urinary obstructive symptoms were quantified by the criteria of the American Urologic Association (AUA). Each patient was contacted during the writing of this report to update postimplant morbidity information. There was no apparent association between the degree of MLH and preimplant prostate volume or AUA score. Intraoperatively, we were able to visualize MLH by transrectal ultrasound and did not notice any particular difficulty placing sources in the MLH tissue or migration of sources out of the tissue. The prescription isodose covered from 81% to 99% of the postimplant CT-defined target volume, achieving adequate dose to the median lobe tissue in all patients. Two of the eight patients developed acute, postimplant urinary retention. The first patient required intermittent self-catheterization for 3 months and then resumed spontaneous urination. MLH does not appear to be a strong contraindication to prostate brachytherapy, and prophylactic resection of hypertrophic tissue in such patients is probably not warranted. Int. J. Cancer (Radiat. Oncol. Invest.) 90, 152-156 (2000).

  12. Percutaneous interstitial brachytherapy for adrenal metastasis: technical report.

    PubMed

    Kishi, Kazushi; Tamura, Shinji; Mabuchi, Yasushi; Sonomura, Tetsuo; Noda, Yasutaka; Nakai, Motoki; Sato, Morio; Ino, Kazuhiko; Yamanaka, Noboru

    2012-09-01

    We developed and evaluated the feasibility of a brachytherapy technique as a safe and effective treatment for adrenal metastasis. Adapting a paravertebral insertion technique in radiofrequency ablation of adrenal tumors, we developed an interstitial brachytherapy for adrenal metastasis achievable on an outpatient basis. Under local anesthesia and under X-ray CT guidance, brachytherapy applicator needles were percutaneously inserted into the target. A treatment plan was created to eradicate the tumor while preserving normal organs including the spinal cord and kidney. We applied this interstitial brachytherapy technique to two patients: one who developed adrenal metastasis as the third recurrence of uterine cervical cancer after reirradiation, and one who developed metachronous multiple metastases from malignant melanoma. The whole procedure was completed in 2.5 hours. There were no procedure-related or radiation-related early/late complications. FDG PET-CT images at two and three months after treatment showed absence of FDG uptake, and no recurrence of the adrenal tumor was observed for over seven months until expiration, and for six months until the present, respectively. This interventional interstitial brachytherapy procedure may be useful as a safe and eradicative treatment for adrenal metastasis.

  13. Achieving Permanency for LGBTQ Youth

    ERIC Educational Resources Information Center

    Jacobs, Jill; Freundlich, Madelyn

    2006-01-01

    This article brings together two significant efforts in the child welfare field: achieving permanence for youth in out-of-home care and meeting the needs of lesbian, gay, bisexual, transgender and questioning (LGBTQ) youth. During the past several years, a national movement has taken place to assure all children and youth have a permanent family…

  14. Permanent-Magnet Meissner Bearing

    NASA Technical Reports Server (NTRS)

    Robertson, Glen A.

    1994-01-01

    Permanent-magnet meissner bearing features inherently stable, self-centering conical configuration. Bearing made stiffer or less stiff by selection of magnets, springs, and spring adjustments. Cylindrical permanent magnets with axial magnetization stacked coaxially on rotor with alternating polarity. Typically, rare-earth magnets used. Magnets machined and fitted together to form conical outer surface.

  15. Permanent-Magnet Meissner Bearing

    NASA Technical Reports Server (NTRS)

    Robertson, Glen A.

    1994-01-01

    Permanent-magnet meissner bearing features inherently stable, self-centering conical configuration. Bearing made stiffer or less stiff by selection of magnets, springs, and spring adjustments. Cylindrical permanent magnets with axial magnetization stacked coaxially on rotor with alternating polarity. Typically, rare-earth magnets used. Magnets machined and fitted together to form conical outer surface.

  16. [The Object Permanence Fallacy.] Commentary.

    ERIC Educational Resources Information Center

    Bradley, Ben S.

    1996-01-01

    Suggests that Greenberg's challenge to the centrality of object permanence in developmental thinking reveals that developmentalists' theories about childhood speak about their own self-images. Notes that developmentalists have been guilty of not only the object permanence fallacy but also the genetic fallacy, or the mistaken belief that describing…

  17. The "Permanent" Patient Problem.

    PubMed

    Bruce, Courtenay R; Majumder, Mary A

    2014-01-01

    Patients who enter the health care system for acute care may become "permanent" patients of the hospital when a lack of resources precludes discharge to the next level of post-acute care. Legal, professional, and ethical norms prohibit physician and acute care hospital "dumping" of these patients. However, limitless use of hospital resources for indefinite stays is untenable. In the absence of hospital policy addressing this specific issue, the availability of financial support will be determined by health care professionals' willingness to advocate for the patient and negotiate with hospital administrators and the ability and willingness of administrators to authorize the use of hospital resources. We propose five mid-level ethical principles to guide advocacy and administrative decision-making about provision of financial support for post-acute care for those patients who cannot afford it. We use two actual, de-identified cases to illustrate how these principles can be used to make reasoned, consistent decisions about the provision of post-acute financial support. © 2014 American Society of Law, Medicine & Ethics, Inc.

  18. SU-E-T-378: Evaluation of An Analytical Model for the Inter-Seed Attenuation Effect in 103-Pd Multi-Seed Implant Brachytherapy

    SciTech Connect

    Safigholi, H; Soliman, A; Song, W; Meigooni, A Soleimani; Han, D

    2015-06-15

    Purpose: Brachytherapy treatment planning systems based on TG-43 protocol calculate the dose in water and neglects the heterogeneity effect of seeds in multi-seed implant brachytherapy. In this research, the accuracy of a novel analytical model that we propose for the inter-seed attenuation effect (ISA) for 103-Pd seed model is evaluated. Methods: In the analytical model, dose perturbation due to the ISA effect for each seed in an LDR multi-seed implant for 103-Pd is calculated by assuming that the seed of interest is active and the other surrounding seeds are inactive. The cumulative dosimetric effect of all seeds is then summed using the superposition principle. The model is based on pre Monte Carlo (MC) simulated 3D kernels of the dose perturbations caused by the ISA effect. The cumulative ISA effect due to multiple surrounding seeds is obtained by a simple multiplication of the individual ISA effect by each seed, the effect of which is determined by the distance from the seed of interest. This novel algorithm is then compared with full MC water-based simulations (FMCW). Results: The results show that the dose perturbation model we propose is in excellent agreement with the FMCW values for a case with three seeds separated by 1 cm. The average difference of the model and the FMCW simulations was less than 8%±2%. Conclusion: Using the proposed novel analytical ISA effect model, one could expedite the corrections due to the ISA dose perturbation effects during permanent seed 103-Pd brachytherapy planning with minimal increase in time since the model is based on multiplications and superposition. This model can be applied, in principle, to any other brachytherapy seeds. Further work is necessary to validate this model on a more complicated geometry as well.

  19. Brachytherapy in the treatment of recurrent aggressive falcine meningiomas.

    PubMed

    Abou Al-Shaar, Hussam; Almefty, Kaith K; Abolfotoh, Mohammad; Arvold, Nils D; Devlin, Phillip M; Reardon, David A; Loeffler, Jay S; Al-Mefty, Ossama

    2015-09-01

    Recurrent aggressive falcine meningiomas are uncommon tumors that recur despite receiving extensive surgery and radiation therapy (RT). We have utilized brachytherapy as a salvage treatment in two such patients with a unique implantation technique. Both patients had recurrence of WHO Grade II falcine meningiomas despite multiple prior surgical and RT treatments. Radioactive I-125 seeds were made into strands and sutured into a mesh implant, with 1 cm spacing, in a size appropriate to cover the cavity and region of susceptible falcine dura. Following resection the vicryl mesh was implanted and fixed to the margins of the falx. Implantation in this interhemispheric space provides good dose conformality with targeting of at-risk tissue and minimal radiation exposure to normal neural tissues. The patients are recurrence free 31 and 10 months after brachytherapy treatment. Brachytherapy was an effective salvage treatment for the recurrent aggressive falcine meningiomas in our two patients.

  20. The needs for brachytherapy source calibrations in the United States

    NASA Astrophysics Data System (ADS)

    Coursey, B. M.; Goodman, L. J.; Hoppes, D. D.; Loevinger, R.; McLaughlin, W. L.; Soares, C. G.; Weaver, J. T.

    1992-02-01

    Brachytherapy sources of beta and gamma radiation ("brachy" is from the Greek, meaning "near") have a long history of use in interstitial, intracavitary, intraluminal, and ocular radiation therapy. In the past the US national standards for these sources were often specified in activity or milligram radium equivalent. With the introduction of new radionuclide sources to replace radium, source strength calibrations are now expressed as air kerma rate at a meter. In this paper, we review the NIST standards for brachytherapy sources, list some of the common radionuclides and source encapsulations in use in the US radiology community, and describe the latest NIST work, in collaboration with several US medical institutions, on a method of two- and three-dimensional dose mapping of brachytherapy sources using radiochromic films.

  1. Brachytherapy in the treatment of skin cancer: an overview.

    PubMed

    Skowronek, Janusz

    2015-10-01

    The incidence of skin cancer worldwide is constantly growing and it is the most frequently diagnosed tumor. Brachytherapy (BT) in particular localizations is a valuable tool of the exact radiation depot inside the tumor mass. In localizations such as the face, skull skin and inoperable tumors, relapses after surgery, radiotherapy are usually not suitable for primary or secondary invasive treatment. Brachytherapy is a safe procedure for organs at risk according to rapid fall of a dose outside the axis of the applicator with satisfactory dose localization inside the target. The complications rate is acceptable and treatment costs are low. In some tumors (great skin lesions in the scalp, near eyes or on the nose) BT allows for a great dose reduction in surrounding healthy tissues. Brachytherapy provides minimal dose delivery to surrounding healthy tissue, thus enabling good functional and cosmetic results. Treatment is possible almost in all cases on an outpatient basis.

  2. p-type silicon detector for brachytherapy dosimetry.

    PubMed

    Piermattei, A; Azario, L; Monaco, G; Soriani, A; Arcovito, G

    1995-06-01

    The sensitivity of a cylindrical p-type silicon detector was studied by means of air and water measurements using different photon beams. A lead filter cap around the diode was used to minimize the dependence of the detector response as a function of the brachytherapy photon energy. The radial dose distribution of a high-activity 192Ir source in a brachytherapy phantom was measured by means of the shielded diode and the agreement of these data with theoretical evaluations confirms the method used to compensate diode response in the intermediate energy range. The diode sensitivity was constant over a wide range of dose rates of clinical interest; this allowed one to have a small detector calibrated in terms of absorbed dose in a medium. Theoretical evaluations showed that a single shielding filter around the p-type diode is sufficient to obtain accurate dosimetry for 192Ir, 137Cs, and 60Co brachytherapy sources.

  3. Brachytherapy in the treatment of skin cancer: an overview

    PubMed Central

    2015-01-01

    The incidence of skin cancer worldwide is constantly growing and it is the most frequently diagnosed tumor. Brachytherapy (BT) in particular localizations is a valuable tool of the exact radiation depot inside the tumor mass. In localizations such as the face, skull skin and inoperable tumors, relapses after surgery, radiotherapy are usually not suitable for primary or secondary invasive treatment. Brachytherapy is a safe procedure for organs at risk according to rapid fall of a dose outside the axis of the applicator with satisfactory dose localization inside the target. The complications rate is acceptable and treatment costs are low. In some tumors (great skin lesions in the scalp, near eyes or on the nose) BT allows for a great dose reduction in surrounding healthy tissues. Brachytherapy provides minimal dose delivery to surrounding healthy tissue, thus enabling good functional and cosmetic results. Treatment is possible almost in all cases on an outpatient basis. PMID:26759545

  4. Interstitial rotating shield brachytherapy for prostate cancer

    SciTech Connect

    Adams, Quentin E. Xu, Jinghzu; Breitbach, Elizabeth K.; Li, Xing; Rockey, William R.; Kim, Yusung; Wu, Xiaodong; Flynn, Ryan T.; Enger, Shirin A.

    2014-05-15

    Purpose: To present a novel needle, catheter, and radiation source system for interstitial rotating shield brachytherapy (I-RSBT) of the prostate. I-RSBT is a promising technique for reducing urethra, rectum, and bladder dose relative to conventional interstitial high-dose-rate brachytherapy (HDR-BT). Methods: A wire-mounted 62 GBq{sup 153}Gd source is proposed with an encapsulated diameter of 0.59 mm, active diameter of 0.44 mm, and active length of 10 mm. A concept model I-RSBT needle/catheter pair was constructed using concentric 50 and 75 μm thick nickel-titanium alloy (nitinol) tubes. The needle is 16-gauge (1.651 mm) in outer diameter and the catheter contains a 535 μm thick platinum shield. I-RSBT and conventional HDR-BT treatment plans for a prostate cancer patient were generated based on Monte Carlo dose calculations. In order to minimize urethral dose, urethral dose gradient volumes within 0–5 mm of the urethra surface were allowed to receive doses less than the prescribed dose of 100%. Results: The platinum shield reduced the dose rate on the shielded side of the source at 1 cm off-axis to 6.4% of the dose rate on the unshielded side. For the case considered, for the same minimum dose to the hottest 98% of the clinical target volume (D{sub 98%}), I-RSBT reduced urethral D{sub 0.1cc} below that of conventional HDR-BT by 29%, 33%, 38%, and 44% for urethral dose gradient volumes within 0, 1, 3, and 5 mm of the urethra surface, respectively. Percentages are expressed relative to the prescription dose of 100%. For the case considered, for the same urethral dose gradient volumes, rectum D{sub 1cc} was reduced by 7%, 6%, 6%, and 6%, respectively, and bladder D{sub 1cc} was reduced by 4%, 5%, 5%, and 6%, respectively. Treatment time to deliver 20 Gy with I-RSBT was 154 min with ten 62 GBq {sup 153}Gd sources. Conclusions: For the case considered, the proposed{sup 153}Gd-based I-RSBT system has the potential to lower the urethral dose relative to HDR-BT by 29

  5. Aspects of dosimetry and clinical practice of skin brachytherapy: The American Brachytherapy Society working group report.

    PubMed

    Ouhib, Zoubir; Kasper, Michael; Perez Calatayud, Jose; Rodriguez, Silvia; Bhatnagar, Ajay; Pai, Sujatha; Strasswimmer, John

    2015-01-01

    Nonmelanoma skin cancers (NMSCs) are the most common type of human malignancy. Although surgical techniques are the standard treatment, radiation therapy using photons, electrons, and brachytherapy (BT) (radionuclide-based and electronic) has been an important mode of treatment in specific clinical situations. The purpose of this work is to provide a clinical and dosimetric summary of the use of BT for the treatment of NMSC and to describe the different BT approaches used in treating cutaneous malignancies. A group of experts from the fields of radiation oncology, medical physics, and dermatology, who specialize in managing cutaneous malignancies reviewed the literature and compiled their clinical experience regarding the clinical and dosimetric aspects of skin BT. A dosimetric and clinical review of both high dose rate ((192)Ir) and electronic BT treatment including surface, interstitial, and custom mold applicators is given. Patient evaluation tools such as staging, imaging, and patient selection criteria are discussed. Guidelines for clinical and dosimetric planning, appropriate margin delineation, and applicator selection are suggested. Dose prescription and dose fractionation schedules, as well as prescription depth are discussed. Commissioning and quality assurance requirements are also outlined. Given the limited published data for skin BT, this article is a summary of the limited literature and best practices currently in use for the treatment of NMSC. Copyright © 2015 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.

  6. Current state of the art brachytherapy treatment planning dosimetry algorithms

    PubMed Central

    Pantelis, E; Karaiskos, P

    2014-01-01

    Following literature contributions delineating the deficiencies introduced by the approximations of conventional brachytherapy dosimetry, different model-based dosimetry algorithms have been incorporated into commercial systems for 192Ir brachytherapy treatment planning. The calculation settings of these algorithms are pre-configured according to criteria established by their developers for optimizing computation speed vs accuracy. Their clinical use is hence straightforward. A basic understanding of these algorithms and their limitations is essential, however, for commissioning; detecting differences from conventional algorithms; explaining their origin; assessing their impact; and maintaining global uniformity of clinical practice. PMID:25027247

  7. Imaging method for monitoring delivery of high dose rate brachytherapy

    DOEpatents

    Weisenberger, Andrew G; Majewski, Stanislaw

    2012-10-23

    A method for in-situ monitoring both the balloon/cavity and the radioactive source in brachytherapy treatment utilizing using at least one pair of miniature gamma cameras to acquire separate images of: 1) the radioactive source as it is moved in the tumor volume during brachytherapy; and 2) a relatively low intensity radiation source produced by either an injected radiopharmaceutical rendering cancerous tissue visible or from a radioactive solution filling a balloon surgically implanted into the cavity formed by the surgical resection of a tumor.

  8. Validation of GPUMCD for low-energy brachytherapy seed dosimetry

    SciTech Connect

    Hissoiny, Sami; Ozell, Benoit; Despres, Philippe; Carrier, Jean-Francois

    2011-07-15

    Purpose: To validate GPUMCD, a new package for fast Monte Carlo dose calculations based on the GPU (graphics processing unit), as a tool for low-energy single seed brachytherapy dosimetry for specific seed models. As the currently accepted method of dose calculation in low-energy brachytherapy computations relies on severe approximations, a Monte Carlo based approach would result in more accurate dose calculations, taking in to consideration the patient anatomy as well as interseed attenuation. The first step is to evaluate the capability of GPUMCD to reproduce low-energy, single source, brachytherapy calculations which could ultimately result in fast and accurate, Monte Carlo based, brachytherapy dose calculations for routine planning. Methods: A mixed geometry engine was integrated to GPUMCD capable of handling parametric as well as voxelized geometries. In order to evaluate GPUMCD for brachytherapy calculations, several dosimetry parameters were computed and compared to values found in the literature. These parameters, defined by the AAPM Task-Group No. 43, are the radial dose function, the 2D anisotropy function, and the dose rate constant. These three parameters were computed for two different brachytherapy sources: the Amersham OncoSeed 6711 and the Imagyn IsoStar IS-12501. Results: GPUMCD was shown to yield dosimetric parameters similar to those found in the literature. It reproduces radial dose functions to within 1.25% for both sources in the 0.5< r <10 cm range. The 2D anisotropy function was found to be within 3% at r = 5 cm and within 4% at r = 1 cm. The dose rate constants obtained were within the range of other values reported in the literature.Conclusion: GPUMCD was shown to be able to reproduce various TG-43 parameters for two different low-energy brachytherapy sources found in the literature. The next step is to test GPUMCD as a fast clinical Monte Carlo brachytherapy dose calculations with multiple seeds and patient geometry, potentially providing

  9. [Guidelines for external radiotherapy and brachytherapy: 2nd edition].

    PubMed

    Mahé, M-A; Barillot, I; Chauvet, B

    2016-09-01

    In 2007, a first edition was published with the objective to produce guidelines for optimization, harmonization and homogenization of practices in external radiation therapy in France. The second edition, including brachytherapy, has the same objective and takes into account recent technologic improvements (intensity modulation radiation therapy, stereotactic radiotherapy, and 3-dimension brachytherapy) and results of literature. The first part is about daily use of general principles (quality, security, image-guided radiation therapy) and the second is to describe each treatment step in main cancers.

  10. Dosimetric characteristics of a new unit for electronic skin brachytherapy

    PubMed Central

    Garcia-Martinez, Teresa; Chan, Jan-Pieter; Perez-Calatayud, Jose

    2014-01-01

    Purpose Brachytherapy with radioactive high dose rate (HDR) 192Ir source is applied to small skin cancer lesions, using surface applicators, i.e. Leipzig or Valencia type. New developments in the field of radiotherapy for skin cancer include electronic brachytherapy. This technique involves the placement of an HDR X-ray source close to the skin, therefore combining the benefits of brachytherapy with the reduced shielding requirements and targeted energy of low energy X-rays. Recently, the Esteya® Electronic Brachytherapy System (Esteya EBS, Elekta AB-Nucletron, Stockholm, Sweden) has been developed specifically for HDR brachytherapy treatment of surface lesions. The system provides radionuclide free HDR brachytherapy by means of a small 69.5 kV X-ray source. The purpose of this study is to obtain the dosimetric characterization required for clinical implementation, providing the detailed methodology to perform the commissioning. Material and methods Flatness, symmetry and penumbra, percentage of depth dose (PDD), kV stability, HVL, output, spectrum, linearity, and leakage have been evaluated for a set of applicators (from 10 mm to 30 mm in diameter). Results Flatness and symmetry resulted better than 5% with around 1 mm of penumbra. The depth dose gradient is about 7%/mm. A kV value of 68.4 ± 1.0 kV (k = 1) was obtained, in good agreement with manufacturer data (69.5 kV). HVL was 1.85 mm Al. Dose rate for a typical 6 Gy to 7 Gy prescription resulted about 3.3 Gy/min and the leakage value was < 100 µGy/min. Conclusions The new Esteya® Electronic Brachytherapy System presents excellent flatness and penumbra as with the Valencia applicator case, combined with an improved PDD, allowing treatment of lesions of up to a depth of 5 mm in combination with reduced treatment duration. The Esteya unit allows HDR brachytherapy superficial treatment within a minimally shielded environment due its low energy. PMID:24790622

  11. Epimacular brachytherapy for wet AMD: current perspectives

    PubMed Central

    Casaroli-Marano, Ricardo P; Alforja, Socorro; Giralt, Joan; Farah, Michel E

    2014-01-01

    Age-related macular degeneration (AMD) is considered the most common cause of blindness in the over-60 age group in developed countries. There are basically two forms of presentation: geographic (dry or atrophic) and wet (neovascular or exudative). Geographic atrophy accounts for approximately 85%–90% of ophthalmic frames and leads to a progressive degeneration of the retinal pigment epithelium and the photoreceptors. Wet AMD causes the highest percentage of central vision loss secondary to disease. This neovascular form involves an angiogenic process in which newly formed choroidal vessels invade the macular area. Today, intravitreal anti-angiogenic drugs attempt to block the angiogenic events and represent a major advance in the treatment of wet AMD. Currently, combination therapy for wet AMD includes different forms of radiation delivery. Epimacular brachytherapy (EMBT) seems to be a useful approach to be associated with current anti-vascular endothelial growth factor agents, presenting an acceptable efficacy and safety profile. However, at the present stage of research, the results of the clinical trials carried out to date are insufficient to justify extending routine use of EMBT for the treatment of wet AMD. PMID:25210436

  12. Epimacular brachytherapy for wet AMD: current perspectives.

    PubMed

    Casaroli-Marano, Ricardo P; Alforja, Socorro; Giralt, Joan; Farah, Michel E

    2014-01-01

    Age-related macular degeneration (AMD) is considered the most common cause of blindness in the over-60 age group in developed countries. There are basically two forms of presentation: geographic (dry or atrophic) and wet (neovascular or exudative). Geographic atrophy accounts for approximately 85%-90% of ophthalmic frames and leads to a progressive degeneration of the retinal pigment epithelium and the photoreceptors. Wet AMD causes the highest percentage of central vision loss secondary to disease. This neovascular form involves an angiogenic process in which newly formed choroidal vessels invade the macular area. Today, intravitreal anti-angiogenic drugs attempt to block the angiogenic events and represent a major advance in the treatment of wet AMD. Currently, combination therapy for wet AMD includes different forms of radiation delivery. Epimacular brachytherapy (EMBT) seems to be a useful approach to be associated with current anti-vascular endothelial growth factor agents, presenting an acceptable efficacy and safety profile. However, at the present stage of research, the results of the clinical trials carried out to date are insufficient to justify extending routine use of EMBT for the treatment of wet AMD.

  13. Radiotherapy and brachytherapy for recurrent colorectal cancer

    SciTech Connect

    Nag, S. )

    1991-05-01

    Radical surgical excision of locoregional recurrence of colorectal carcinoma usually produces the best survival and should be attempted whenever possible. However, recurrences are often unresectable; hence palliative local therapy may be indicated. There are several options for the radiation therapy of local, unresectable, recurrent, or metastatic colorectal cancer. Whole pelvis irradiation of 4,000-5,000 cGy followed by a coned-down boost of 1,000-1,500 cGy generally provides good symptomatic palliation in 80-90% of patients, but long-term control or cure is rarely achieved. External beam irradiation of 2,000-3,000 cGy to the whole liver with or without concurrent chemotherapy may be used for palliation of metastatic disease to the liver. A combination of intraoperative radiation therapy applied directly to the tumor bed and external beam irradiation may improve local control and survival rates. Multiple options are available for the intraoperative use of brachytherapy which can deliver high radiation doses to the residual tumor, or tumor bed, sparing normal tissue.

  14. Dosimetry of two new interstitial brachytherapy sources

    NASA Astrophysics Data System (ADS)

    Saidi, Pooneh; Sadeghi, Mahdi

    2011-01-01

    With increased demand for low 103Pd (palladium) seed sources, to treat prostate and eye cancers, new sources have been designed and introduced. This article presents the two new palladium brachytherapy sources, IR03-103Pd and IR04-103Pd that have been developed at Nuclear Science and Technology Research Institute. The dosimetry parameters such as the dose rate constant Λ, the radial dose function g(r), and the anisotropy function F(r,θ), around the sources have been characterized using Version 5 Monte Carlo radiation transport code in accordance with the update AAPM Task Group No. 43 report (TG-43U1). The results indicated the dose rate constant of 0.689±0.02 and 0.667±0.02 cGy h-1 U-1 for the IR03-103Pd and IR04-103Pd sources respectively, which are in acceptable agreement with other commercial seeds. The calculated results were compared with published results for those of other source manufacturers. However, they show an acceptable dose distribution, using for clinical applications is pending experimental dosimetry.

  15. Periodic permanent magnet focused klystron

    DOEpatents

    Ferguson, Patrick; Read, Michael; Ives, R Lawrence

    2015-04-21

    A periodic permanent magnet (PPM) klystron has beam transport structures and RF cavity structures, each of which has permanent magnets placed substantially equidistant from a beam tunnel formed about the central axis, and which are also outside the extent of a cooling chamber. The RF cavity sections also have permanent magnets which are placed substantially equidistant from the beam tunnel, but which include an RF cavity coupling to the beam tunnel for enhancement of RF carried by an electron beam in the beam tunnel.

  16. Topology optimized permanent magnet systems

    NASA Astrophysics Data System (ADS)

    Bjørk, R.; Bahl, C. R. H.; Insinga, A. R.

    2017-09-01

    Topology optimization of permanent magnet systems consisting of permanent magnets, high permeability iron and air is presented. An implementation of topology optimization for magnetostatics is discussed and three examples are considered. The Halbach cylinder is topology optimized with iron and an increase of 15% in magnetic efficiency is shown. A topology optimized structure to concentrate a homogeneous field is shown to increase the magnitude of the field by 111%. Finally, a permanent magnet with alternating high and low field regions is topology optimized and a Λcool figure of merit of 0.472 is reached, which is an increase of 100% compared to a previous optimized design.

  17. Postoperative interstitial brachytherapy in eyelid cancer: long term results and assessment of Cosmesis After Interstitial Brachytherapy scale

    PubMed Central

    Basu, Trinanjan; Chaudhary, Suresh; Chaukar, Devendra; Nadkarni, Mandar; GN, Manjunatha

    2014-01-01

    Purpose To analyse feasibility and safety of postoperative interstitial brachytherapy (IBRT) in patients of eyelid cancer treated primarily by surgical excision. Material and methods In this series, 8 patients with eyelid cancer were treated using postoperative interstitial brachytherapy. Patients were followed up for local control, cosmetic outcome, and acute and late toxicities. Cosmetic outcome was measured using a 6 point indigenous Cosmesis After Interstitial Brachytherapy (CAIB) scale. Results The patients were between 23-82 years (median: 71 years). There were 3 females and 5 males, and 3 patients had lesions in upper eyelid. Postoperative high-dose-rate brachytherapy was used in all with 2 catheters implanted in most of them (6 out of 8). Local control was calculated from end of treatment to last follow-up. At last follow-up, all patients remained locally controlled. Two patients had nodal recurrence 6 months after interstitial brachytherapy and were salvaged effectively by external beam radiotherapy. At last follow-up, 7 patients were loco-regionally controlled and one was lost to follow up. All patients had Radiation Therapy Oncology Group (RTOG) grade 1 acute toxicity and 2 had grade 1 Common Terminology Criteria for Adverse Events (CTCAE) version.3 late toxicities. The cosmesis score for the whole group ranged between 0-1 indicating excellent to very good cosmesis. Conclusions Postoperative high-dose-rate brachytherapy resulted in excellent disease control and cosmesis without significant acute or late toxicities. It is an effective modality for treatment of eyelid cancers in selected patients. Future prospective studies with the validation of CAIB scale would give us more insight to this effective yet often ignored modality of IBRT. PMID:25834578

  18. Patient-specific Monte Carlo dose calculations for 103Pd breast brachytherapy

    NASA Astrophysics Data System (ADS)

    Miksys, N.; Cygler, J. E.; Caudrelier, J. M.; Thomson, R. M.

    2016-04-01

    This work retrospectively investigates patient-specific Monte Carlo (MC) dose calculations for 103Pd permanent implant breast brachytherapy, exploring various necessary assumptions for deriving virtual patient models: post-implant CT image metallic artifact reduction (MAR), tissue assignment schemes (TAS), and elemental tissue compositions. Three MAR methods (thresholding, 3D median filter, virtual sinogram) are applied to CT images; resulting images are compared to each other and to uncorrected images. Virtual patient models are then derived by application of different TAS ranging from TG-186 basic recommendations (mixed adipose and gland tissue at uniform literature-derived density) to detailed schemes (segmented adipose and gland with CT-derived densities). For detailed schemes, alternate mass density segmentation thresholds between adipose and gland are considered. Several literature-derived elemental compositions for adipose, gland and skin are compared. MC models derived from uncorrected CT images can yield large errors in dose calculations especially when used with detailed TAS. Differences in MAR method result in large differences in local doses when variations in CT number cause differences in tissue assignment. Between different MAR models (same TAS), PTV {{D}90} and skin {{D}1~\\text{c{{\\text{m}}3}}} each vary by up to 6%. Basic TAS (mixed adipose/gland tissue) generally yield higher dose metrics than detailed segmented schemes: PTV {{D}90} and skin {{D}1~\\text{c{{\\text{m}}3}}} are higher by up to 13% and 9% respectively. Employing alternate adipose, gland and skin elemental compositions can cause variations in PTV {{D}90} of up to 11% and skin {{D}1~\\text{c{{\\text{m}}3}}} of up to 30%. Overall, AAPM TG-43 overestimates dose to the PTV ({{D}90} on average 10% and up to 27%) and underestimates dose to the skin ({{D}1~\\text{c{{\\text{m}}3}}} on average 29% and up to 48%) compared to the various MC models derived using the post-MAR CT images studied

  19. Patient-specific Monte Carlo dose calculations for (103)Pd breast brachytherapy.

    PubMed

    Miksys, N; Cygler, J E; Caudrelier, J M; Thomson, R M

    2016-04-07

    This work retrospectively investigates patient-specific Monte Carlo (MC) dose calculations for (103)Pd permanent implant breast brachytherapy, exploring various necessary assumptions for deriving virtual patient models: post-implant CT image metallic artifact reduction (MAR), tissue assignment schemes (TAS), and elemental tissue compositions. Three MAR methods (thresholding, 3D median filter, virtual sinogram) are applied to CT images; resulting images are compared to each other and to uncorrected images. Virtual patient models are then derived by application of different TAS ranging from TG-186 basic recommendations (mixed adipose and gland tissue at uniform literature-derived density) to detailed schemes (segmented adipose and gland with CT-derived densities). For detailed schemes, alternate mass density segmentation thresholds between adipose and gland are considered. Several literature-derived elemental compositions for adipose, gland and skin are compared. MC models derived from uncorrected CT images can yield large errors in dose calculations especially when used with detailed TAS. Differences in MAR method result in large differences in local doses when variations in CT number cause differences in tissue assignment. Between different MAR models (same TAS), PTV [Formula: see text] and skin [Formula: see text] each vary by up to 6%. Basic TAS (mixed adipose/gland tissue) generally yield higher dose metrics than detailed segmented schemes: PTV [Formula: see text] and skin [Formula: see text] are higher by up to 13% and 9% respectively. Employing alternate adipose, gland and skin elemental compositions can cause variations in PTV [Formula: see text] of up to 11% and skin [Formula: see text] of up to 30%. Overall, AAPM TG-43 overestimates dose to the PTV ([Formula: see text] on average 10% and up to 27%) and underestimates dose to the skin ([Formula: see text] on average 29% and up to 48%) compared to the various MC models derived using the post-MAR CT images

  20. Neurocognitive function and quality of life in patients with newly diagnosed brain metastasis after treatment with intra-operative cesium-131 brachytherapy: a prospective trial.

    PubMed

    Pham, Anthony; Yondorf, Menachem Z; Parashar, Bhupesh; Scheff, Ronald J; Pannullo, Susan C; Ramakrishna, Rohan; Stieg, Philip E; Schwartz, Theodore H; Wernicke, A Gabriella

    2016-03-01

    Intraoperative permanent Cesium-131 (Cs-131) brachytherapy can provide a viable alternative to WBRT with excellent response rates and minimal toxicity. This study reports the results of the prospective trial of the impact of intraoperative Cs-131 on neurocognitive function and quality of life (QoL) in patients with resected brain metastases. Between 2010 and 2012, 24 patients with newly diagnosed metastasis to the brain were accrued on a prospective protocol and treated with Cs-131 brachytherapy seeds after surgical resection. Physicians administered the mini-mental status examination (MMSE) and functional assessment of cancer therapy-brain (FACT-Br) questionnaire to all patients before treatment and again every 2 months for the duration of 6 months with additional follow-up again at 12 months. Wilcoxon rank sum test was used to analyze statistically significant changes in MMSE over time and paired t test was used to analyze changes in FACT-BR. There was a statistical improvement in overall FACT-BR score at 4 and 6 months of follow-up when compared to baseline (162 vs. 143, P = 0.004; 164 vs. 143, P = 0.005 respectively) with a non-significant trend toward improvement at 2 and 12 months (154 vs. 143, P = 0.067; 159 vs. 149, P = 0.4). MMSE score was statistically improved at 4 and up to 12 months compared to pre-treatment MMSE (30 vs. 29, P = 0.017; 30 vs. 29, P = 0.001 respectively). Patients with brain metastasis who received intra-operative permanent Cs-131 brachytherapy implants saw an improvement of their neurocognitive status and self-assessment of QoL. In addition to the excellent local control of metastasis, this approach may contribute to the improvements in cognitive function and QOL.

  1. Tattoos and Permanent Make-Up

    MedlinePlus

    ... Information by Audience For Women Tattoos and Permanent Make-up Share Tweet Linkedin Pin it More sharing options ... your skin. Permanent tattoos last a lifetime . Permanent Make-Up : A needle inserts colored ink into your skin ...

  2. SU-E-T-546: Use of Implant Volume for Quality Assurance of Low Dose Rate Brachytherapy Treatment Plans

    SciTech Connect

    Wilkinson, D; Kolar, M

    2014-06-01

    Purpose: To analyze the application of volume implant (V100) data as a method for a global check of low dose rate (LDR) brachytherapy plans. Methods: Treatment plans for 335 consecutive patients undergoing permanent seed implants for prostate cancer and for 113 patients treated with plaque therapy for ocular melanoma were analyzed. Plaques used were 54 COMS (10 to 20 mm, notched and regular) and 59 Eye Physics EP917s with variable loading. Plots of treatment time x implanted activity per unit dose versus v100 ^.667 were made. V100 values were obtained using dose volume histograms calculated by the treatment planning systems (Variseed 8.02 and Plaque Simulator 5.4). Four different physicists were involved in planning the prostate seed cases; two physicists for the eye plaques. Results: Since the time and dose for the prostate cases did not vary, a plot of implanted activity vs V100 ^.667 was made. A linear fit with no intercept had an r{sup 2} = 0.978; more than 94% of the actual activities fell within 5% of the activities calculated from the linear fit. The greatest deviations were in cases where the implant volumes were large (> 100 cc). Both COMS and EP917 plaque linear fits were good (r{sup 2} = .967 and .957); the largest deviations were seen for large volumes. Conclusions: The method outlined here is effective for checking planning consistency and quality assurance of two types of LDR brachytherapy treatment plans (temporary and permanent). A spreadsheet for the calculations enables a quick check of the plan in situations were time is short (e.g. OR-based prostate planning)

  3. Current status of brachytherapy in Korea: a national survey of radiation oncologists.

    PubMed

    Kim, Haeyoung; Kim, Joo Young; Kim, Juree; Park, Won; Kim, Young Seok; Kim, Hak Jae; Kim, Yong Bae

    2016-07-01

    The aim of the present study was to acquire information on brachytherapy resources in Korea through a national survey of radiation oncologists. Between October 2014 and January 2015, a questionnaire on the current status of brachytherapy was distributed to all 86 radiation oncology departments in Korea. The questionnaire was divided into sections querying general information on human resources, brachytherapy equipment, and suggestions for future directions of brachytherapy policy in Korea. The response rate of the survey was 88.3%. The average number of radiation oncologists per center was 2.3. At the time of survey, 28 centers (36.8%) provided brachytherapy to patients. Among the 28 brachytherapy centers, 15 (53.5%) were located in in the capital Seoul and its surrounding metropolitan areas. All brachytherapy centers had a high-dose rate system using (192)Ir (26 centers) or (60)Co (two centers). Among the 26 centers using (192)Ir sources, 11 treated fewer than 40 patients per year. In the two centers using (60)Co sources, the number of patients per year was 16 and 120, respectively. The most frequently cited difficulties in performing brachytherapy were cost related. A total of 21 centers had a plan to sustain the current brachytherapy system, and four centers noted plans to upgrade their brachytherapy system. Two centers stated that they were considering discontinuation of brachytherapy due to cost burdens of radioisotope source replacement. The present study illustrated the current status of brachytherapy in Korea. Financial difficulties were the major barriers to the practice of brachytherapy.

  4. Modeling the impact of prostate edema on LDR brachytherapy: a Monte Carlo dosimetry study based on a 3D biphasic finite element biomechanical model

    NASA Astrophysics Data System (ADS)

    Mountris, K. A.; Bert, J.; Noailly, J.; Rodriguez Aguilera, A.; Valeri, A.; Pradier, O.; Schick, U.; Promayon, E.; Gonzalez Ballester, M. A.; Troccaz, J.; Visvikis, D.

    2017-03-01

    Prostate volume changes due to edema occurrence during transperineal permanent brachytherapy should be taken under consideration to ensure optimal dose delivery. Available edema models, based on prostate volume observations, face several limitations. Therefore, patient-specific models need to be developed to accurately account for the impact of edema. In this study we present a biomechanical model developed to reproduce edema resolution patterns documented in the literature. Using the biphasic mixture theory and finite element analysis, the proposed model takes into consideration the mechanical properties of the pubic area tissues in the evolution of prostate edema. The model’s computed deformations are incorporated in a Monte Carlo simulation to investigate their effect on post-operative dosimetry. The comparison of Day1 and Day30 dosimetry results demonstrates the capability of the proposed model for patient-specific dosimetry improvements, considering the edema dynamics. The proposed model shows excellent ability to reproduce previously described edema resolution patterns and was validated based on previous findings. According to our results, for a prostate volume increase of 10-20% the Day30 urethra D10 dose metric is higher by 4.2%-10.5% compared to the Day1 value. The introduction of the edema dynamics in Day30 dosimetry shows a significant global dose overestimation identified on the conventional static Day30 dosimetry. In conclusion, the proposed edema biomechanical model can improve the treatment planning of transperineal permanent brachytherapy accounting for post-implant dose alterations during the planning procedure.

  5. 10 CFR 35.2406 - Records of brachytherapy source accountability.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Records of brachytherapy source accountability. 35.2406 Section 35.2406 Energy NUCLEAR REGULATORY COMMISSION MEDICAL USE OF BYPRODUCT MATERIAL Records § 35.2406... from storage, the name of the individual who removed them from storage, and the location of use; and...

  6. 21 CFR 892.5730 - Radionuclide brachytherapy source.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Radionuclide brachytherapy source. 892.5730 Section 892.5730 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT